Enhanced stethoscope device and methods

ABSTRACT

An enhanced stethoscope device and method for operating the enhanced stethoscope are provided. The enhanced stethoscope device generally operates by providing stethoscope sensors, ultrasonic sensors, and other sensors to obtain a series of measurements about a subject. The series of measurements may be correlated, such as by machine learning, to extract clinically relevant information. Also described are systems and methods for ultrasonic beamsteering by interference of an audio signal with an ultrasonic signal.

CROSS-REFERENCE

The present application is a continuation of U.S. application Ser. No.16/038,070, entitled “ENHANCED STETHOSCOPE DEVICES AND APPLICATIONS”,filed on Jul. 17, 2018 (attorney docket no. 38075-730.301), which is acontinuation of U.S. application Ser. No. 15/678,789, entitled “ENHANCEDSTETHOSCOPE DEVICES AND APPLICATIONS”, filed on Aug. 16, 2017 (attorneydocket no. 38075-730.201), U.S. application Ser. No. 15/678,789,entitled “ENHANCED STETHOSCOPE DEVICES AND APPLICATIONS”, filed on Aug.16, 2017 (attorney docket no. 38075-730.201), which claims priority toU.S. Provisional Application No. 62/376,300, entitled “EnhancedStethoscope Device, Method, and Platform for Measurement of Physiology”,filed on Aug. 17, 2016 (attorney docket no. 38075-730.101), whichapplications are incorporated herein by reference in their entiretiesfor all purposes.

BACKGROUND

The traditional stethoscope is ubiquitously used in the chain of medicalcare. However, in isolation it is only capable of assessing respirationand heart rate; blood pressure measurements are possible when thestethoscope is used in conjunction with a sphygmomanometer. Atraditional stethoscope head contains a diaphragm that mechanicallyamplifies audio signals in the 0.01 Hz to 3 kHz range. For medical use,operators fix the head of the stethoscope adjacent to the phenomenonbeing observed (e.g. against the chest to measure respiration). Thediaphragm transmits the sound coupled into the stethoscope head from thefeatures (such as the heart or lungs) into a set of ear pieces. Theoperator then interprets this sound and manually records thismeasurement. Studies have shown that these measurements have a strongdependence on the level of training for the operators, as well as theaudio environment in which the measurements are taken.

Electronic stethoscopes have attempted to address the limitations oftraditional stethoscopes in loud environments, such as the emergencydepartment. They convert the mechanical vibrations incident on thediaphragm into electronic signals that can be readily amplified andtransmitted to the earpiece worn by the operator. However, the humanoperator is still required to interpret the audio signals to deducephysiometric parameters such as heart rate and respiration rate.

In contrast, ultrasound imaging equipment has been developed to automatesome of this data collection and interpretation. For example, ultrasoundimagers can extract adult or fetal heart rate from recorded images orDoppler ultrasound. These imagers measure high frequency echoes thatpenetrate and reflect off of tissues within a body. A number ofstrategies have been developed to modulate the frequency of the sound toperform tomography using these ultrasound instruments. For example, highfrequencies generate higher resolution images at shallower depths (e.g.subcutaneous tissue, lungs, vasculature) and lower frequencies generatelower resolution images at deeper depths (e.g. visceral organs).Ultrasound is used for a variety of diagnostic imaging purposesincluding examination and monitoring of infection, trauma, bowelobstruction, cardiac disorder, pregnancy staging, and fetal health.Though its versatility would make the ultrasound a particularlyeffective tool for use in point-of-care medicine, in the developingworld, in wilderness expeditions, and in spaceflight, the typically highcost, power-requirements, and size of ultrasound equipment haveprevented its adoption for many scenarios.

Furthermore, unlike stethoscopes, current ultrasound imagers requiresubstantial training to use, yet still suffer from substantialinter-operator variability. These limitations have allowed ultrasound toaugment, but not replace, stethoscopes.

SUMMARY

Owing to the complementary diagnostic information provided bystethoscopes and ultrasound systems, there is a need for systems andmethods that utilize both of these technologies. Ideally, such systemsand methods would also measure and incorporate information regardingphysiological parameters, such as heart rate, blood pressure, bodytemperature, respiration rate, or SpO₂ (saturation of hemoglobin withO₂).

The systems and methods described herein generally relate tostethoscopes providing enhanced functionality over the stethoscopes thatare commonly used by medical professionals. An enhanced stethoscopedevice and method for operating the enhanced stethoscope are provided.The enhanced stethoscope device generally operates by providingstethoscope sensors, ultrasonic sensors, and other sensors to obtain aseries of measurements about a subject. The series of measurements maybe correlated, such as by machine learning, to extract clinicallyrelevant information. Also described are systems and methods forultrasonic beamsteering by interference of an audio signal with anultrasonic signal.

In a first broad aspect, a stethoscope device may comprise a stethoscopehead. The audio head may comprise a mechanical diaphragm. The mechanicaldiaphragm may receive a stethoscopic audio signal from an object. Thestethoscope device may further comprise a first ultrasonic transducer.The first ultrasonic transducer may transmit a first transmittedultrasonic imaging signal to the object at a first frequency and receivea first received ultrasonic imaging signal from the object at the firstfrequency. The stethoscope device may further comprise a secondultrasonic transducer. The second ultrasonic transducer may transmit asecond transmitted ultrasonic imaging signal to the object at a secondfrequency different from the first frequency and receive a secondreceived ultrasonic imaging signal from the object at the secondfrequency. The first and second ultrasonic imaging transducers maytransmit and receive simultaneously with one another.

The frequency of the first transmitted ultrasonic imaging signal may beselected from the group consisting of: 100 kHz, 200 kHz, 300 kHz, 400kHz, 500 kHz, 650 kHz, 700 kHz, 800 kHz, 850 kHz, 900 kHz, 1 MHz, 2 MHz,3 MHz, 5.5 MHz, 6 MHz, 8 MHz, and 11 MHz. The frequency of the secondtransmitted ultrasonic imaging signal may be in the frequency range of0.5 Mhz-30 MHz. The frequency of the first received ultrasonic imagingsignal may be selected from the group consisting of: 100 kHz, 200 kHz,300 kHz, 400 kHz, 500 kHz, 650 kHz, 700 kHz, 800 kHz, 850 kHz, 900 kHz,1 MHz, 2 MHz, 3 MHz, 5.5 MHz, 6 MHz, 8 MHz, and 11 MHz. The frequency ofthe second received ultrasonic imaging signal may be in the frequencyrange of 0.5 Mhz-30 MHz. The frequency of the first transmittedultrasonic imaging signal may be in the frequency range of 0.5 MHz-30MHz and the frequency of the second transmitted ultrasonic imagingsignal may be in the frequency range of 0.5 MHz-30 MHz and may bedistinct from the frequency of the first transmitted ultrasonic imagingsignal. The frequency of the first received ultrasonic imaging signalmay be in the frequency range of 0.5 MHz-30 MHz and the frequency of thesecond received ultrasonic imaging signal may be in the frequency rangeof 0.5 MHz-30 MHz and may be distinct from the frequency of the firstreceived ultrasonic imaging signal.

The first received ultrasonic imaging signal may be normalized by thesecond received ultrasonic imaging signal.

The first ultrasonic transducer may comprise an element selected fromthe group consisting of: a lead zirconate titanate (PZT) element, apolyvinylidine fluoride (PVDF) element, a piezoelectric micromachinedultrasound transducer (PMUT) element, and a capacitive micromachinedultrasonic transducer (CMUT) element. The second ultrasonic transducermay comprise an element selected from the group consisting of: a PZTelement, a PVDF element, a PMUT element, and a CMUT element.

The first ultrasonic transducer may have a bandwidth that partiallyoverlaps with the bandwidth of at least one other ultrasonic imagingsensor.

The stethoscope device may comprise a housing coupled to one or more ofthe stethoscope head, the first ultrasonic transducer, and the secondultrasonic transducer. One or more of the stethoscope head, the firstultrasonic transducer, and the second ultrasonic transducer may bedetachably coupled to the housing. One or more of the stethoscope head,the first ultrasonic transducer, and the second ultrasonic transducermay be physically coupled to the housing. One or more of the stethoscopehead, the first ultrasonic transducer, and the second ultrasonictransducer may be functionally coupled to the housing.

The stethoscope device may further comprise a non-stethoscopic,non-ultrasonic sensor for detecting a non-stethoscopic, non-ultrasonicsignal. The non-stethoscopic, non-ultrasonic sensor may be selected fromthe group consisting of: a non-stethoscopic audio sensor, a temperaturesensor, an optical sensor, an electrical sensor, and an electrochemicalsensor. The non-stethoscopic, non-ultrasonic sensor may be configured todetect a signal originating from the group consisting of: a bodytemperature, a respiration rate, a respiration quality, a respirationpathology, a blood pressure level, a blood glucose concentration level,a blood gas concentration level, and a blood oxygenation saturation(spO₂) level.

The stethoscope head may be functionally coupled to the first and secondultrasonic transducers.

The stethoscope device may comprise a battery. The stethoscope devicemay comprise a power connector for receiving electrical power. Thestethoscope device may comprise an inductive power coil for receivingelectrical power. The stethoscope device may comprise an inductive powercoil for transmitting and receiving data.

The stethoscope device may comprise a control for operating the devicein one or more of a stethoscopic mode, an ultrasonic imaging mode, or anon-stethoscopic, non-ultrasonic mode. The control may comprise a userinterface. The user interface may be configured to provide a user withfeedback based on the stethoscopic signal, the ultrasonic signal, or thenon-stethoscopic, non-ultrasonic signal. The user interface may comprisea touchscreen device.

The stethoscope device may comprise a wireless networking modality. Thewireless networking modality may be configured to communicate thestethoscopic audio signal, received ultrasonic signal, ornon-stethoscopic, non-ultrasonic signal to a peripheral device.

The stethoscope device may comprise a microphone and speaker. Themicrophone and speaker may enable communication between an operator ofthe enhanced stethoscope device and the enhanced stethoscope device.

In a second broad aspect, a stethoscope device may comprise astethoscope head. The stethoscope head may comprise a mechanicaldiaphragm. The mechanical diaphragm may receive a stethoscopic audiosignal from an object. The stethoscope device may further comprise anultrasonic transducer. The ultrasonic transducer may transmit atransmitted ultrasonic imaging signal to the object and receive areceived ultrasonic imaging signal from the object. The stethoscopedevice may further comprise a non-stethoscopic, non-ultrasonic sensor.The non-stethoscopic, non-ultrasonic sensor may detect anon-stethoscopic, non-ultrasonic signal from the object.

The stethoscope device may comprise a housing coupled to the stethoscopehead, the ultrasonic transducer, and the non-stethoscopic,non-ultrasonic sensor. One or more of the stethoscope head, theultrasonic transducer, and the non-stethoscopic, non-ultrasonic sensormay be detachably coupled to the housing. One or more of the stethoscopehead, the ultrasonic transducer, and the non-stethoscopic,non-ultrasonic sensor may be physically coupled to the housing. One ormore of the stethoscope head, the ultrasonic transducer, and thenon-stethoscopic, non-ultrasonic sensor may be functionally coupled tothe housing.

The received ultrasonic imaging signal received from the object may be ascattered signal of the transmitted ultrasonic imaging signal.

The non-stethoscopic, non-ultrasonic sensor may be selected from thegroup consisting of: a non-stethoscopic audio sensor, a temperaturesensor, an optical sensor, an electrical sensor, a chemical sensor, andan electrochemical sensor. The non-stethoscopic, non-ultrasonic sensormay be configured to detect a signal corresponding with one or more of:a body temperature, a respiration rate, a respiration volume, arespiration quality, a respiratory pathology, a blood pressure level, ablood glucose concentration, a blood gas concentration level, and ablood oxygenation saturation (spO₂) level.

The ultrasonic transducer may be attached to the stethoscope head.

The stethoscope device may comprise a rechargeable or non-rechargeablebattery. The stethoscope device may comprise a power connector forreceiving electrical power. The stethoscope device may comprise aninductive power coil for receiving electrical power. The stethoscopedevice may comprise an inductive power coil for transmitting andreceiving data.

The stethoscope device may comprise a control for operating the devicein one or more of a stethoscopic mode, an ultrasonic imaging mode, anon-stethoscopic, non-ultrasonic mode. The control may comprise a userinterface. The user interface may be configured to provide a user withfeedback based on the stethoscopic signal, ultrasonic signal, ornon-stethoscopic, non-ultrasonic signal. The user interface may comprisea display. The display may display a 2-dimensional representation of asample being imaged. The user interface may comprise a touchscreendevice.

The stethoscope device may comprise a wireless networking modality. Thewireless networking modality may be configured to communicate thestethoscopic audio signal, received ultrasonic signal, ornon-stethoscopic, non-ultrasonic signal to a peripheral device.

The stethoscope device may comprise a microphone and speaker. Themicrophone and speaker may enable communication between an operator ofthe enhanced stethoscope device and the enhanced stethoscope device.

In a third broad aspect, a stethoscope device may comprise a stethoscopehead. The stethoscope head may comprise a mechanical diaphragm. Themechanical diaphragm may receive a stethoscopic audio signal from anobject. The stethoscope device may further comprise an ultrasonictransducer. The ultrasonic transducer may transmit a transmittedultrasonic imaging signal to the object and receive a receivedultrasonic imaging signal from the object. The stethoscope device mayfurther comprise a model. The model may correlate the stethoscopic audiosignal and the received ultrasonic imaging signal.

The stethoscope device may comprise a housing coupled to the stethoscopehead and ultrasonic transducer. One or both of the stethoscope head andthe ultrasonic transducer may be detachably coupled to the housing. Oneor both of the stethoscope head and the ultrasonic transducer may bephysically coupled to the housing. One or both of the stethoscope headand ultrasonic transducer may be functionally coupled to the housing.

The stethoscope device may comprise a non-stethoscopic, non-ultrasonicsensor for detecting a non-stethoscopic, non-ultrasonic signal. Thenon-stethoscopic, non-ultrasonic sensor may be selected from the groupconsisting of: a non-stethoscopic audio sensor, a temperature sensor, anoptical sensor, an electrical sensor, a chemical sensor and anelectrochemical sensor. The non-stethoscopic, non-ultrasonic sensor maybe configured to detect a signal corresponding with from one or more of:a body temperature, a respiration rate, a blood pressure level, and ablood oxygenation saturation (spO₂) level.

The model may correlate a first signal selected from the groupconsisting of: (a) a stethoscopic audio signal, (b) an ultrasonicimaging signal, and (c) a non-ultrasonic signal; with a second signalselected from the group consisting of: (x) a stethoscopic audio signal,(y) an ultrasonic imaging signal, and (z) a non-ultrasonic signal;thereby generating an extracted feature parameter.

The model may correlate the first and second signals by: convolving thefirst signal with a first weighting function to form a first weightedsignal; convolving the second signal with a second weighting function toform a second weighted signal; and performing auto-correlation orcross-correlation on the first and second weighted signals to generatethe extracted feature parameter.

The model may correlate the first and second signals by: transformingthe first and second signals, respectively, with one or more of (i) aFourier transform, (ii) a Z-transform, (iii) a wavelet transform, (iv) acosine series, (v) a sine series, or (vi) a Taylor series; to form firstand second transformed signals, respectively; and cross-correlating orauto-correlating the first and second transformed signals to generate afeature parameter.

The model may correlate the first and second signals by: encoding thefirst and second signals; and mapping the first and second signals to aset of features using a machine learning technique. The machine learningtechnique may be selected from the group consisting of: a Diabolonetwork, a neural network, and a sparse dictionary.

The ultrasonic transducer may be attached to the head of thestethoscope.

The stethoscope device may comprise a rechargeable or non-rechargeablebattery. The stethoscope device may comprise a power connector forreceiving electrical power. The stethoscope device may comprise aninductive power coil for receiving electrical power. The stethoscopedevice may comprise an inductive power coil for transmitting andreceiving data.

The stethoscope device may comprise a control for operating the devicein one or more of a stethoscopic mode, an ultrasonic imaging mode, or anon-stethoscopic, non-ultrasonic mode. The control may comprise a userinterface. The user interface may be configured to provide a user withfeedback based on one or more of the stethoscopic signal, the ultrasonicsignal, or the non-stethoscopic, non-ultrasonic signal. The userinterface may comprise a touchscreen device.

The stethoscope device may comprise a wireless networking modality. Thewireless networking modality may be configured to communicate one ormore of the stethoscopic audio signal, the received ultrasonic signal,or the non-stethoscopic, non-ultrasonic signal to a peripheral device.

The stethoscope device may comprise a microphone and speaker. Themicrophone and speaker may enable communication between an operator ofthe enhanced stethoscope device and the enhanced stethoscope device.

In a fourth broad aspect, a stethoscope device may comprise astethoscope head. The stethoscope head may comprise a mechanicaldiaphragm. The mechanical diaphragm may receive a stethoscopic audiosignal from an object. The stethoscope device may further comprise anultrasonic transducer. The ultrasonic transducer may transmit atransmitted ultrasonic imaging signal to the object and receive areceived ultrasonic imaging signal from the object. The stethoscopedevice may further comprise an audio transducer. The audio transducermay transmit an audio signal to the object. The stethoscope device mayfurther comprise an interference circuit. The interference circuit mayinterfere the transmitted ultrasonic imaging signal with the audiosignal to steer the ultrasonic imaging signal to the object.

The stethoscope device may comprise a housing coupled to one or more ofthe stethoscope head, the ultrasonic transducer, the audio transducer,and the interference circuit. One or more of the stethoscope head, theultrasonic transducer, the audio transducer, and the interferencecircuit may be detachably coupled to the housing. One or more of thestethoscope head, the ultrasonic transducer, the audio transducer, andthe interference circuit may be physically coupled to the housing. Oneor more of the stethoscope head, the ultrasonic transducer, the audiotransducer, and the interference circuit may be functionally coupled tothe housing.

The interference circuit may interfere the transmitted ultrasonicimaging signal with the audio signal based on a model of the objectresponse to the audio signal. The model may correlate the ultrasonicimaging signal with the audio signal and generate an extracted featureparameter.

The model may correlate the ultrasonic imaging signal and the audiosignal by: convolving the ultrasonic imaging signal with a firstweighting function to form a weighted ultrasonic imaging signal;convolving the audio signal with a second weighting function to form aweighted audio signal; and performing auto-correlation orcross-correlation on the weighted ultrasonic imaging signal and theweight audio signal to generate a feature parameter.

The model may correlate the ultrasonic imaging signal and the audiosignal by: transforming the ultrasonic imaging and audio signals,respectively, with one or more of (i) a Fourier transform, (ii) aZ-transform, (iii) a wavelet transform, (iv) a cosine series, (v) a sineseries, or (vi) a Taylor series; to form transformed ultrasonic imagingand transformed audio signals, respectively; and cross-correlating orauto-correlating the transformed ultrasonic imaging signal and thetransformed audio signal to generate a feature parameter.

The model may correlate the ultrasonic imaging signal and the audiosignal by: encoding the ultrasonic imaging signal and the audio signal;and mapping the ultrasonic imaging signal and the audio signal to a setof features using a machine learning technique. The machine learningtechnique may be selected from the group consisting of: a Diabolonetwork, a neural network, and a sparse dictionary.

The stethoscope device may comprise a non-stethoscopic, non-ultrasonicsensor for detecting a non-stethoscopic, non-ultrasonic signal. Thenon-stethoscopic, non-ultrasonic sensor may be selected from the groupconsisting of: a non-stethoscopic audio sensor, a temperature sensor, anoptical sensor, an electrical sensor, a chemical sensor, and anelectrochemical sensor. The non-stethoscopic, non-ultrasonic sensor maybe configured to detect a signal corresponding with the group consistingof: a body temperature, a respiration rate, a respiration quality, arespiration pathology, a blood pressure level, a blood glucoseconcentration level, a blood gas concentration level, and a bloodoxygenation saturation (spO₂) level.

The ultrasonic transducer may be detachably or non-detachably attachedto the head of the stethoscope. The ultrasonic transducer may beattached to an acoustic matching layer. The ultrasonic transducer may bedetachably or non-detachably attached to the head of the stethoscope.

The stethoscope device may comprise a rechargeable or non-rechargeablebattery. The stethoscope device may comprise a power connector forreceiving electrical power. The stethoscope device may comprise aninductive power coil for receiving electrical power. The stethoscopedevice may comprise an inductive power coil for transmitting andreceiving data.

The stethoscope device may comprise a control for operating the devicein one or more of a stethoscopic mode, an ultrasonic imaging mode, and anon-stethoscopic, non-ultrasonic mode. The control may comprise a userinterface. The user interface may be configured to provide a user withfeedback based on one or more of the stethoscopic signal, the ultrasonicsignal, and the non-stethoscopic, non-ultrasonic signal. The userinterface may comprise a touchscreen device.

The stethoscope device may comprise a wireless networking modality. Thewireless networking modality may be configured to communicate one ormore of the stethoscopic audio signal, the received ultrasonic signal,and the non-stethoscopic, non-ultrasonic signal to a peripheral device.

The stethoscope device may comprise a microphone and speaker. Themicrophone and speaker may enable communication between an operator ofthe enhanced stethoscope device and the enhanced stethoscope device.

In a fifth broad aspect, a method may comprise receiving a stethoscopicaudio signal from an object. The stethoscopic audio signal may bereceived by a stethoscope head comprising a mechanical diaphragm. Themethod may further comprise transmitting a first transmitted ultrasonicimaging signal to the object at a first frequency and receiving a firstreceived ultrasonic imaging signal from the object at the firstfrequency. The first ultrasonic imaging signal may be transmitted andreceived by a first ultrasonic transducer. The method may furthercomprise transmitting a second transmitted ultrasonic imaging signal tothe object at a second frequency different from the first frequency andreceiving a second received ultrasonic imaging signal from the object atthe second frequency. The second ultrasonic imaging signal may betransmitted and received by a second ultrasonic transducer. The firstand second ultrasonic transducers may transmit and receivesimultaneously with one another.

The frequency of the first transmitted ultrasonic imaging signal may beselected from the group consisting of: 100 kHz, 200 kHz, 300 kHz, 400kHz, 500 kHz, 650 kHz, 700 kHz, 800 kHz, 850 kHz, 900 k Hz, 1 MHz, 2MHz, 3 MHz, 5.5 MHz, 6 MHz, 8 MHz, and 11 MHz; and the frequency of thesecond transmitted ultrasonic imaging signal may be in the frequencyrange of 0.5 Mhz-30 MHz. The frequency of the first transmittedultrasonic imaging signal may be selected from the group consisting of:100 kHz, 200 kHz, 300 kHz, 400 kHz, 500 kHz, 650 kHz, 700 kHz, 800 kHz,850 kHz, 900 kHz, 1 MHz, 2 MHz, 3 MHz, 5.5 MHz, 6 MHz, 8 MHz, and 11MHz; and the frequency of the second transmitted ultrasonic imagingsignal may be in the frequency range of 0.5 Mhz-30 MHz. The frequency ofthe first received ultrasonic imaging signal may be selected from thegroup consisting of: 100 kHz, 200 kHz, 300 kHz, 400 kHz, 500 kHz, 650kHz, 700 kHz, 800 kHz, 850 kHz, 900 kHz, 1 MHz, 2 MHz, 3 MHz, 5.5 MHz, 6MHz, 8 MHz, and 11 MHz; and the frequency of the second receivedultrasonic imaging signal may be in the frequency range of 0.5 Mhz-30MHz. The frequency of the first transmitted ultrasonic imaging signalmay be in the frequency range of 0.5 MHz-30 MHz and the frequency of thesecond transmitted ultrasonic imaging signal may be in the frequencyrange of 0.5 MHz-30 MHz and is distinct from the frequency of the firsttransmitted ultrasonic imaging signal. The frequency of the firstreceived ultrasonic imaging signal may be in the frequency range of 0.5MHz-30 MHz and the frequency of the second received ultrasonic imagingsignal may be in the frequency range of 0.5 MHz-30 MHz and is distinctfrom the frequency of the first received ultrasonic imaging signal.

The first received ultrasonic imaging signal may be normalized by thesecond received ultrasonic imaging signal.

The first ultrasonic transducer may comprise an element selected fromthe group consisting of: a lead zirconate titanate (PZT) element, apolyvinylidine fluoride (PVDF) element, a piezoelectric micromachinedultrasound transducer (PMUT) element, and a capacitive micromachinedultrasonic transducer (CMUT) element; and the second ultrasonictransducer may comprise an element selected from the group consistingof: a PZT element, a PVDF element, a PMUT element, and a CMUT element.

The first ultrasonic transducer may have a bandwidth that partiallyoverlaps with the bandwidth of at least one other ultrasonic imagingsensor.

The method may further comprise coupling a housing to one or more of thestethoscope head, the first ultrasonic transducer, and the secondultrasonic transducer. One or more of the stethoscope head, the firstultrasonic transducer, and the second ultrasonic transducer may bedetachably coupled to the housing. One or more of the stethoscope head,the first ultrasonic transducer, and the second ultrasonic transducermay be physically coupled to the housing. One or more of the stethoscopehead, the first ultrasonic transducer, and the second ultrasonictransducer may functionally coupled to the housing.

The method may further comprise detecting a non-stethoscopic,non-ultrasonic signal. The non-stethoscopic, non-ultrasonic signal maybe detected by a non-stethoscopic, non-ultrasonic sensor. Thenon-stethoscopic, non-ultrasonic sensor may be selected from the groupconsisting of: a non-stethoscopic audio sensor, a temperature sensor, anoptical sensor, an electrical sensor, and an electrochemical sensor. Thenon-stethoscopic, non-ultrasonic sensor may be configured to detect asignal originating from the group consisting of: a body temperature, arespiration rate, a respiration quality, a respiration pathology, ablood pressure level, a blood glucose concentration level, a blood gasconcentration level, and a blood oxygenation saturation (spO₂) level.

The stethoscope head may be functionally coupled to the first and secondultrasonic transducers.

The method may further comprise providing power to the stethoscope head,first ultrasonic imaging transducer, and second ultrasonic imagingtransducer. The power may be provided by a battery. The power may beprovided by a power connector for receiving electrical power. The powermay be provided by an inductive power coil for receiving electricalpower.

The method may further comprise transmitting and receiving data.Transmitting and receiving data may be performed by an inductive powercoil for transmitting and receiving data.

The method may further comprise operating the device in one or more of astethoscopic mode, an ultrasonic imaging mode, or a non-stethoscopic,non-ultrasonic mode. Operation of the device may be performed by acontrol. The control may comprise a user interface. The user interfacemay be configured to provide a user with feedback based on thestethoscopic signal, the ultrasonic signal, or the non-stethoscopic,non-ultrasonic signal. The user interface may comprise a touchscreendevice.

The method may further comprise communicating the stethoscopic audiosignal, received ultrasonic signal, or non-stethoscopic, non-ultrasonicsignal to a peripheral device. The communication may be by a wirelessnetworking modality.

The method may further comprise enabling communication between anoperator of the stethoscope device and the stethoscope device. Thecommunication may be enabled by a microphone and speaker.

In a sixth broad aspect, a method may comprise receiving a stethoscopicaudio signal from an object. The stethoscopic audio signal may bereceived by a stethoscope comprising a mechanical diaphragm. The methodmay further comprise transmitting a transmitted ultrasonic imagingsignal to the object and receiving a received ultrasonic imaging signalfrom the object. The ultrasonic imaging signal may be transmitted andreceived by an ultrasonic transducer. The method may further comprisedetecting a non-stethoscopic, non-ultrasonic signal from the object. Thenon-stethoscopic, non-ultrasonic signal may be detected by anon-stethoscopic, non-ultrasonic sensor.

The method may further comprise coupling a housing to the stethoscopehead, the ultrasonic transducer, and the non-stethoscopic,non-ultrasonic sensor. One or more of the stethoscope head, theultrasonic transducer, and the non-stethoscopic, non-ultrasonic sensormay be detachably coupled to the housing. One or more of the stethoscopehead, the ultrasonic transducer, and the non-stethoscopic,non-ultrasonic sensor may be physically coupled to the housing. One ormore of the stethoscope head, the ultrasonic transducer, and thenon-stethoscopic, non-ultrasonic sensor may be functionally coupled tothe housing.

The received ultrasonic imaging signal received from the object may be ascattered signal of the transmitted ultrasonic imaging signal.

The non-stethoscopic, non-ultrasonic sensor may be selected from thegroup consisting of: a non-stethoscopic audio sensor, a temperaturesensor, an optical sensor, an electrical sensor, a chemical sensor, andan electrochemical sensor. The non-stethoscopic, non-ultrasonic sensormay be configured to detect a signal corresponding with one or more of:a body temperature, a respiration rate, a respiration volume, arespiration quality, a respiratory pathology, a blood pressure level, ablood glucose concentration, a blood gas concentration level, and ablood oxygenation saturation (spO₂) level.

The ultrasonic transducer may be attached to the stethoscope head.

The method may further comprise providing power to the stethoscope head,first ultrasonic imaging transducer, and second ultrasonic imagingtransducer. The power may be provided by a battery. The power may beprovided by a power connector for receiving electrical power. The powermay be provided by an inductive power coil for receiving electricalpower.

The method may further comprise transmitting and receiving data.Transmitting and receiving data may be performed by an inductive powercoil for transmitting and receiving data.

The method may further comprise operating the device in one or more of astethoscopic mode, an ultrasonic imaging mode, or a non-stethoscopic,non-ultrasonic mode. Operation of the device may be performed by acontrol. The control may comprise a user interface. The user interfacemay be configured to provide a user with feedback based on thestethoscopic signal, the ultrasonic signal, or the non-stethoscopic,non-ultrasonic signal. The user interface may comprise a touchscreendevice.

The method may further comprise communicating the stethoscopic audiosignal, received ultrasonic signal, or non-stethoscopic, non-ultrasonicsignal to a peripheral device. The communication may be by a wirelessnetworking modality.

The method may further comprise enabling communication between anoperator of the stethoscope device and the stethoscope device. Thecommunication may be enabled by a microphone and speaker.

In a seventh broad aspect, a method may comprise receiving astethoscopic audio signal from an object. The stethoscopic audio signalmay be received by a stethoscope comprising a mechanical diaphragm. Themethod may further comprise transmitting a transmitted ultrasonicimaging signal to the object and receiving a received ultrasonic imagingsignal from the object. The ultrasonic imaging signal may be transmittedand received by an ultrasonic transducer. The method may furthercomprise correlating the stethoscopic audio signal and the receivedultrasonic imaging signal. The stethoscopic audio signal and receivedultrasonic imaging signal may be correlated by a model.

The method may further comprise coupling a housing to the stethoscopehead and ultrasonic transducer. One or both of the stethoscope head andthe ultrasonic transducer may be detachably coupled to the housing. Oneor both of the stethoscope head and the ultrasonic transducer may bephysically coupled to the housing. One or both of the stethoscope headand ultrasonic transducer may be functionally coupled to the housing.

The method may further comprise detecting a non-stethoscopic,non-ultrasonic signal. The non-stethoscopic, non-ultrasonic signal maybe detected by a non-stethoscopic, non-ultrasonic sensor. Thenon-stethoscopic, non-ultrasonic sensor may be selected from the groupconsisting of: a non-stethoscopic audio sensor, a temperature sensor, anoptical sensor, an electrical sensor, a chemical sensor and anelectrochemical sensor. The non-stethoscopic, non-ultrasonic sensor maybe configured to detect a signal corresponding with from one or more of:a body temperature, a respiration rate, a blood pressure level, and ablood oxygenation saturation (spO₂) level.

The model may correlate a first signal selected from the groupconsisting of: (a) a stethoscopic audio signal, (b) an ultrasonicimaging signal, and (c) a non-ultrasonic signal; with a second signalselected from the group consisting of: (x) a stethoscopic audio signal,(y) an ultrasonic imaging signal, and (z) a non-ultrasonic signal;thereby generating an extracted feature parameter.

The model may correlate the first and second signals by: convolving thefirst signal with a first weighting function to form a first weightedsignal; convolving the second signal with a second weighting function toform a second weighted signal; and performing auto-correlation orcross-correlation on the first and second weighted signals to generatethe extracted feature parameter.

The model may correlate the first and second signals by: transformingthe first and second signals, respectively, with one or more of (i) aFourier transform, (ii) a Z-transform, (iii) a wavelet transform, (iv) acosine series, (v) a sine series, or (vi) a Taylor series; to form firstand second transformed signals, respectively; and cross-correlating orauto-correlating the first and second transformed signals to generate afeature parameter.

The model may correlate the first and second signals by: encoding thefirst and second signals; and mapping the first and second signals to aset of features using a machine learning technique. The machine learningtechnique may be selected from the group consisting of: a Diabolonetwork, a neural network, and a sparse dictionary.

The ultrasonic transducer may be attached to the head of thestethoscope.

The method may further comprise providing power to the stethoscope head,first ultrasonic imaging transducer, and second ultrasonic imagingtransducer. The power may be provided by a battery. The power may beprovided by a power connector for receiving electrical power. The powermay be provided by an inductive power coil for receiving electricalpower.

The method may further comprise transmitting and receiving data.Transmitting and receiving data may be performed by an inductive powercoil for transmitting and receiving data.

The method may further comprise operating the device in one or more of astethoscopic mode, an ultrasonic imaging mode, or a non-stethoscopic,non-ultrasonic mode. Operation of the device may be performed by acontrol. The control may comprise a user interface. The user interfacemay be configured to provide a user with feedback based on thestethoscopic signal, the ultrasonic signal, or the non-stethoscopic,non-ultrasonic signal. The user interface may comprise a touchscreendevice.

The method may further comprise communicating the stethoscopic audiosignal, received ultrasonic signal, or non-stethoscopic, non-ultrasonicsignal to a peripheral device. The communication may be by a wirelessnetworking modality.

The method may further comprise enabling communication between anoperator of the stethoscope device and the stethoscope device. Thecommunication may be enabled by a microphone and speaker.

In an eighth broad aspect, a method may comprise receiving astethoscopic audio signal from an object. The stethoscopic audio signalmay be received by a stethoscope comprising a mechanical diaphragm. Themethod may further comprise transmitting a transmitted ultrasonicimaging signal to the object and receiving a received ultrasonic imagingsignal from the object. The ultrasonic imaging signal may be transmittedand received by an ultrasonic transducer. The method may furthercomprise transmitting an audio signal to the object. The audio signalmay be transmitted by an audio transducer. The method may furthercomprise interfering the transmitted ultrasonic imaging signal with theaudio signal to steer the ultrasonic imaging signal to the object. Thetransmitted ultrasonic imaging signal may be interfered with the audiosignal by an interference circuit.

The method may further comprise coupling a housing to one or more of thestethoscope head, the ultrasonic transducer, the audio transducer, andthe interference circuit. One or more of the stethoscope head, theultrasonic transducer, the audio transducer, and the interferencecircuit may be detachably coupled to the housing. One or more of thestethoscope head, the ultrasonic transducer, the audio transducer, andthe interference circuit may be physically coupled to the housing. Oneor more of the stethoscope head, the ultrasonic transducer, the audiotransducer, and the interference circuit may be functionally coupled tothe housing.

The interference circuit may interfere the transmitted ultrasonicimaging signal with the audio signal based on a model of the objectresponse to the audio signal. The model may correlate the ultrasonicimaging signal with the audio signal and generates an extracted featureparameter.

The model may correlate the ultrasonic imaging signal and the audiosignal by: convolving the ultrasonic imaging signal with a firstweighting function to form a weighted ultrasonic imaging signal;convolving the audio signal with a second weighting function to form aweighted audio signal; and performing auto-correlation orcross-correlation on the weighted ultrasonic imaging signal and theweight audio signal to generate a feature parameter.

The model may correlate the ultrasonic imaging signal and the audiosignal by: transforming the ultrasonic imaging and audio signals,respectively, with one or more of (i) a Fourier transform, (ii) aZ-transform, (iii) a wavelet transform, (iv) a cosine series, (v) a sineseries, or (vi) a Taylor series; to form transformed ultrasonic imagingand transformed audio signals, respectively; and cross-correlating orauto-correlating the transformed ultrasonic imaging signal and thetransformed audio signal to generate a feature parameter. The model maycorrelate the ultrasonic imaging signal and the audio signal by:encoding the ultrasonic imaging signal and the audio signal; and mappingthe ultrasonic imaging signal and the audio signal to a set of featuresusing a machine learning technique. The machine learning technique maybe selected from the group consisting of: a Diabolo network, a neuralnetwork, and a sparse dictionary.

The method may further comprise detecting a non-stethoscopic,non-ultrasonic signal. The non-stethoscopic, non-ultrasonic signal maybe detected by a non-stethoscopic, non-ultrasonic sensor. Thenon-stethoscopic, non-ultrasonic sensor may be selected from the groupconsisting of: a non-stethoscopic audio sensor, a temperature sensor, anoptical sensor, an electrical sensor, a chemical sensor, and anelectrochemical sensor. The non-stethoscopic, non-ultrasonic sensor maybe configured to detect a signal corresponding with the group consistingof: a body temperature, a respiration rate, a respiration quality, arespiration pathology, a blood pressure level, a blood glucoseconcentration level, a blood gas concentration level, and a bloodoxygenation saturation (spO₂) level.

The ultrasonic transducer may be detachably or non-detachably attachedto the head of the stethoscope. The ultrasonic transducer may beattached to an acoustic matching layer.

The method may further comprise providing power to the stethoscope head,first ultrasonic imaging transducer, and second ultrasonic imagingtransducer. The power may be provided by a battery. The power may beprovided by a power connector for receiving electrical power. The powermay be provided by an inductive power coil for receiving electricalpower.

The method may further comprise transmitting and receiving data.Transmitting and receiving data may be performed by an inductive powercoil for transmitting and receiving data.

The method may further comprise operating the device in one or more of astethoscopic mode, an ultrasonic imaging mode, or a non-stethoscopic,non-ultrasonic mode. Operation of the device may be performed by acontrol. The control may comprise a user interface. The user interfacemay be configured to provide a user with feedback based on thestethoscopic signal, the ultrasonic signal, or the non-stethoscopic,non-ultrasonic signal. The user interface may comprise a touchscreendevice.

The method may further comprise communicating the stethoscopic audiosignal, received ultrasonic signal, or non-stethoscopic, non-ultrasonicsignal to a peripheral device. The communication may be by a wirelessnetworking modality.

The method may further comprise enabling communication between anoperator of the stethoscope device and the stethoscope device. Thecommunication may be enabled by a microphone and speaker.

Additional aspects and advantages of the present disclosure will becomereadily apparent to those skilled in this art from the followingdetailed description, wherein only illustrative embodiments of thepresent disclosure are shown and described. As will be realized, thepresent disclosure is capable of other and different embodiments, andits several details are capable of modifications in various obviousrespects, all without departing from the disclosure. Accordingly, thedrawings and description are to be regarded as illustrative in nature,and not as restrictive.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.To the extent publications and patents or patent applicationsincorporated by reference contradict the disclosure contained in thespecification, the specification is intended to supersede and/or takeprecedence over any such contradictory material.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings (also “Figure” and “FIG.” herein), of which:

FIG. 1 schematically illustrates a stethoscope device comprising astethoscope head.

FIG. 2A schematically illustrates a stethoscope head comprising amechanical diaphragm and a plurality of ultrasonic transducers.

FIG. 2B schematically illustrates simultaneous actuation of theplurality of ultrasonic transducers.

FIG. 3A schematically illustrates actuation of a first ultrasonictransducer of the plurality of ultrasonic transducers at a first timepoint.

FIG. 3B schematically illustrates actuation of a second ultrasonictransducer of the plurality of ultrasonic transducers at a second timepoint.

FIG. 3C schematically illustrates actuation of a third ultrasonictransducer of the plurality of ultrasonic transducers at a third timepoint.

FIG. 3D schematically illustrates actuation of a fourth ultrasonictransducer of the plurality of ultrasonic transducers at a fourth timepoint.

FIG. 4 schematically illustrates a method of forming ultrasonic imagesfrom a plurality of ultrasonic transducers.

FIG. 5A schematically illustrates a side view of a stethoscope headcomprising a mechanical diaphragm, a plurality of ultrasoundtransducers, and a plurality of non-stethoscopic, non-ultrasonicsensors.

FIG. 5B schematically illustrates a perspective view of a stethoscopehead comprising a mechanical diaphragm, a plurality of ultrasoundtransducers, and a plurality of non-stethoscopic, non-ultrasonicsensors.

FIG. 6A schematically illustrates a top view of a stethoscope headcomprising a body, an impedance matching substrate, and a userinterface.

FIG. 6B schematically illustrates a side view of a stethoscope headcomprising a body, an impedance matching substrate, and a userinterface.

FIG. 6C schematically illustrates a bottom view of a stethoscope headcomprising a body, an impedance matching substrate, and a userinterface.

FIG. 7 schematically illustrates use of a stethoscope head comprising auser interface in an interactive imaging mode.

FIG. 8 illustrates a schematic block diagram of a machine learningsystem comprising a pre-processing module and a machine learning module.

FIG. 9 illustrates an exemplary multi-layer autoencoder configured toconvert a set of pre-processed physiological information from thepre-processing module into minimal physiological data.

FIG. 10 illustrates a flowchart representing a process by which minimalphysiological data may be extracted from the input to an autoencoder.

FIG. 11 schematically illustrates a method for extracting features froma stethoscopic audio signal obtained by a mechanical diaphragm, anultrasonic signal obtained by an ultrasonic transducer, and one or morenon-stethoscopic, non-ultrasonic signals obtained by a non-stethoscopic,non-ultrasonic sensor.

FIG. 12 shows how information from the stethoscope device may betransmitted to information systems.

FIG. 13 shows how information from the stethoscope device may beutilized by different individuals or institutions.

FIG. 14 shows an exemplary digital processing device programmed orotherwise configured to operate the stethoscope devices and methodsdescribed herein.

FIG. 15 depicts the use of an enhanced stethoscope device for monitoringblood pressure.

FIG. 16 illustrates a multi-input multi-output (MIMO) correlation fordetermining a physiometric parameter associated with ultrasonic andoptical measurement of a blood bolus.

FIG. 17 illustrates a method for receiving a stethoscopic audio signal,simultaneously transmitting first and second ultrasonic imaging signals,and receiving first and second ultrasonic imaging signals.

FIG. 18 illustrates a method for receiving a stethoscopic audio signal,transmitting and receiving an ultrasonic imaging signal, and detecting anon-stethoscopic, non-ultrasonic imaging signal.

FIG. 19 illustrates a method for receiving a stethoscopic audio signal,transmitting and receiving an ultrasonic imaging signal, and correlatingthe stethoscopic audio signal and the ultrasonic imaging signal.

FIG. 20 illustrates a method for receiving a stethoscopic audio signal,transmitting and receiving an ultrasonic imaging signal, transmitting anaudio signal, and interfering the transmitted ultrasonic imaging signaland the audio signal to steer the ultrasonic imaging signal.

DETAILED DESCRIPTION

While various embodiments of the invention are shown and describedherein, it will be obvious to those skilled in the art that suchembodiments are provided by way of example only. Numerous variations,changes, and substitutions may occur to those skilled in the art withoutdeparting from the invention. It should be understood that variousalternatives to the embodiments of the invention described herein may beemployed.

Where values are described as ranges, it will be understood that suchdisclosure includes the disclosure of all possible sub-ranges withinsuch ranges, as well as specific numerical values that fall within suchranges irrespective of whether a specific numerical value or specificsub-range is expressly stated.

As used herein, like characters refer to like elements.

The term “subject,” as used herein, generally refers to an animal, suchas a mammalian species (e.g., human) or avian (e.g., bird) species, orother organism, such as a plant. The subject can be a vertebrate, amammal, a mouse, a primate, a simian or a human. Animals may include,but are not limited to, farm animals, sport animals, and pets. A subjectcan be a healthy or asymptomatic individual, an individual that has oris suspected of having a disease (e.g., cancer) or a pre-disposition tothe disease, or an individual that is in need of therapy or suspected ofneeding therapy. A subject can be a patient.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as is commonly understood by one of skill in theart to which the claimed subject matter belongs. It is to be understoodthat the foregoing general description and the following detaileddescription are exemplary and explanatory only and are not restrictiveof any subject matter claimed. In this application, the use of thesingular includes the plural unless specifically stated otherwise. Itmust be noted that, as used in the specification and the appendedclaims, the singular forms “a,” “an” and “the” include plural referentsunless the context clearly dictates otherwise. In this application, theuse of “or” means “and/or” unless stated otherwise. Furthermore, use ofthe term “including” as well as other forms, such as “include”,“includes,” and “included,” is not limiting.

The section headings used herein are for organizational purposes onlyand are not to be construed as limiting the subject matter described.

FIG. 1 schematically illustrates a stethoscope device comprising astethoscope head. The stethoscope device 100 may comprise a head 110,tubing 120, and one or two ear pieces 130. The head may comprise amechanical diaphragm, as described herein. The mechanical diaphragm maybe configured to mechanically amplify audio signals. For instance, themechanical diaphragm may amplify audio signals that have a frequencywithin a range from about 0.01 Hz to about 3 kHz. The head may be placedin contact with or in proximity to a sample to be examined, such as apatient's chest, stomach, limb such as an arm or leg, or any other bodypart of the patient. The mechanical diaphragm may amplify audio signalsassociated with one or more biological processes occurring within thepatient. For instance, the mechanical diaphragm may amplify audiosignals associated with a patient's heartbeat, breathing, blood flow,digestion, or any other biological process that produces audio signals.The head may further comprise one or more non-stethoscopic audiosensors, as described herein.

The tubing may direct audio signals that are amplified by the mechanicaldiaphragm of the head to the one or two ear pieces. The tubing maycomprise hollow tubing. The hollow tubing may be filled with air. Thetubing may be flexible.

The one or two ear pieces may be worn within one or two ears of a userof the stethoscope device. A user may be a doctor, nurse, emergencymedical technician, field medic, or any other medical professional. Insome cases, a user may be a person without formal medical training, suchas a friend or relative of a patient or a patient himself or herself.The one or two ear pieces may direct amplified audio signals from themechanical diaphragm to one or two ears of the user. In this manner, theuser may listen directly to the audio signals captured and amplified bythe mechanical diaphragm.

FIG. 2A schematically illustrates a stethoscope head 110 comprising amechanical diaphragm 200 and a plurality of ultrasonic transducers210A-D. The mechanical diaphragm may be implemented on a surface of thestethoscope head or within the stethoscope head. The plurality ofultrasonic transducers may be implemented on a surface of thestethoscope head or within the stethoscope head. Though depicted as fourultrasonic transducers in FIG. 2A, the plurality of ultrasonictransducers may comprise 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, or more than 16 ultrasonic transducers. Each ultrasonic transducerof the plurality of ultrasonic transducers may be a lead zirconatetitante (PZT) transducer, a polyvinylidine fluoride (PVD) transducer, apiezoelectric micromachine ultrasound transducer (PMUT), or a capacitivemicromachine ultrasonic transducer (PMUT), or any other ultrasonictransducer. Each ultrasonic transducer of the plurality may be of thesame type. One or more ultrasonic transducer of the plurality may be ofa different type than other ultrasonic transducer of the plurality.

The stethoscope device may further comprise a housing (not shown in FIG.1 or FIG. 2A). The housing may be coupled to one or more of thestethoscope head, the first ultrasonic transducer, and the secondultrasonic transducer. The housing may be detachably coupled to one ormore of the stethoscope head, the first ultrasonic transducer, and thesecond ultrasonic transducer. The housing may be physically coupled toone or more of the stethoscope head, the first ultrasonic transducer,and the second ultrasonic transducer. The housing may be functionallycoupled to one or more of the stethoscope head, the first ultrasonictransducer, and the second ultrasonic transducer.

Each ultrasonic transducer of the plurality of ultrasonic transducersmay be configured to transmit a transmitted ultrasonic imaging signal toan object. Each ultrasonic transducer of the plurality may be configuredto transmit a transmitted ultrasonic imaging signal having a frequencyof about 100 kHz, about 200 kHz, about 300 kHz, about 400 kHz, about 500kHz, about 650 kHz, about 700 kHz, about 800 kHz, about 850 kHz, about900 kHz, about 1 MHz, about 2 MHz, about 3 MHz, about 5.5 MHz, about 6MHz, about 8 MHz, about 11 MHz, about 15 MHz, about 20 MHz, about 25MHz, or about 30 MHz. Each ultrasonic transducer of the plurality may beconfigured to transmit a transmitted ultrasonic imaging signal having afrequency that is within a range defined by any two of the precedingvalues.

Each ultrasonic transducer of the plurality of ultrasonic transducersmay be configured to receive a received ultrasonic imaging signal froman object. Each ultrasonic transducer of the plurality may be configuredto receive a received ultrasonic imaging signal having a frequency ofabout 100 kHz, about 200 kHz, about 300 kHz, about 400 kHz, about 500kHz, about 650 kHz, about 700 kHz, about 800 kHz, about 850 kHz, about900 kHz, about 1 MHz, about 2 MHz, about 3 MHz, about 5.5 MHz, about 6MHz, about 8 MHz, about 11 MHz, about 15 MHz, about 20 MHz, about 25MHz, or about 30 MHz. Each ultrasonic transducer of the plurality may beconfigured to receive a received ultrasonic imaging signal having afrequency that is within a range defined by any two of the precedingvalues.

Each ultrasonic transducer of the plurality may be configured both totransmit and to receive. Each ultrasonic transducer of the plurality maybe configured to transmit transmitted ultrasonic imaging signals orreceive received ultrasonic imaging signals at a frequency that is thesame as one or more of the frequencies transmitted or received by otherultrasonic transducer of the plurality. Each ultrasonic transducer ofthe plurality may be configured to transmit transmitted ultrasonicimaging signals or receive received ultrasonic imaging signals at afrequency that is different from all of frequencies transmitted orreceived by all other ultrasonic transducer of the plurality. Each ofthe ultrasonic transducer of the plurality may be configured to transmitor receive at the same time as one or more other ultrasonic transducerof the plurality.

For instance, a first transmitted imaging signal of a first ultrasonictransducer of the plurality may have a frequency of about 100 kHz, about200 kHz, about 300 kHz, about 400 kHz, about 500 kHz, about 650 kHz,about 700 kHz, about 800 kHz, about 850 kHz, about 900 kHz, about 1 MHz,about 2 MHz, about 3 MHz, about 5.5 MHz, about 6 MHz, about 8 MHz, orabout 11 MHz. A second transmitted imaging signal of a second ultrasonictransducer of the plurality may have a frequency that is in a range fromabout 0.5 MHz to about 30 MHz. A first received imaging signal of afirst ultrasonic transducer of the plurality may have a frequency ofabout 100 kHz, about 200 kHz, about 300 kHz, about 400 kHz, about 500kHz, about 650 kHz, about 700 kHz, about 800 kHz, about 850 kHz, about900 kHz, about 1 MHz, about 2 MHz, about 3 MHz, about 5.5 MHz, about 6MHz, about 8 MHz, or about 11 MHz. A second received imaging signal of asecond ultrasonic transducer of the plurality may have a frequency thatis in a range from about 0.5 MHz to about 30 MHz.

In another example, a first transmitted imaging signal of a firstultrasonic transducer of the plurality may have a frequency that is in arange from about 0.5 MHz to about 30 MHz. A second transmitted imagingsignal of a second ultrasonic transducer of the plurality may have afrequency that is in a range from about 0.5 MHz to about 30 MHz, butthat is different from the frequency of the first transmitted imagingsignal. A first received imaging signal of a first ultrasonic transducerof the plurality may have a frequency that is in a range from about 0.5MHz to about 30 MHz. A second received imaging signal of a secondultrasonic transducer of the plurality may have a frequency that is in arange from about 0.5 MHz to about 30 MHz, but that is different from thefrequency of the first received imaging signal.

A third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh,twelfth, thirteenth, fourteenth, fifteenth, or sixteenth transmittedimaging signal of a third, fourth, fifth, sixth, seventh, eighth, ninth,tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth ultrasonic transducer, respectively, may have a frequency thatis about 100 kHz, about 200 kHz, about 300 kHz, about 400 kHz, about 500kHz, about 650 kHz, about 700 kHz, about 800 kHz, about 850 kHz, about900 kHz, about 1 MHz, about 2 MHz, about 3 MHz, about 5.5 MHz, about 6MHz, about 8 MHz, or about 11 MHz. The third, fourth, fifth, sixth,seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth,fourteenth, fifteenth, or sixteenth transmitted imaging signal may havea frequency that is within a range described by any two of the precedingvalues. The third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthtransmitted imaging signal may have a value that is in a range fromabout 0.5 MHz to about 30 MHz. The third, fourth, fifth, sixth, seventh,eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth,fifteenth, or sixteenth transmitted imaging signal may have a frequencythat is different from one or more of the frequencies of the first andsecond transmitted imaging signals.

A third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh,twelfth, thirteenth, fourteenth, fifteenth, or sixteenth receivedimaging signal of a third, fourth, fifth, sixth, seventh, eighth, ninth,tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth ultrasonic transducer, respectively, may have a frequency thatis about 100 kHz, about 200 kHz, about 300 kHz, about 400 kHz, about 500kHz, about 650 kHz, about 700 kHz, about 800 kHz, about 850 kHz, about900 kHz, about 1 MHz, about 2 MHz, about 3 MHz, about 5.5 MHz, about 6MHz, about 8 MHz, or about 11 MHz. The third, fourth, fifth, sixth,seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth,fourteenth, fifteenth, or sixteenth received imaging signal may have afrequency that is within a range described by any two of the precedingvalues. The third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthreceived imaging signal may have a value that is in a range from about0.5 MHz to about 30 MHz. The third, fourth, fifth, sixth, seventh,eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth,fifteenth, or sixteenth received imaging signal may have a frequencythat is different from one or more of the frequencies of the first andsecond transmitted imaging signals.

Each ultrasonic transducer of the plurality of transducers may transmittransmitted ultrasonic imaging signals or receive received ultrasonicimaging signals within a bandwidth. The first ultrasonic transducer mayhave a first bandwidth and the second ultrasonic transducer may have asecond bandwidth. The first bandwidth and the second bandwidth mayoverlap. The first bandwidth and the second bandwidth may partiallyoverlap. The first bandwidth and the second bandwidth may not overlap.Similarly, the third, fourth, fifth, sixth, seventh, eighth, ninth,tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth ultrasonic transducers may have third, fourth, fifth, sixth,seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth,fourteenth, fifteenth, or sixteenth bandwidths, respectively. Any one ofthe first, second, third, fourth, fifth, sixth, seventh, eighth, ninth,tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth bandwidths may overlap one another. Any one of the first,second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthbandwidths may partially overlap one another. Any one of the first,second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthbandwidths may not overlap one another.

The received imaging signals may be subjected to pre-processingoperations. For instance, a first received imaging signal may form abasis for normalizing other received imaging signals. A second receivedimaging signal may be normalized by the first received imaging signal. Athird, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh,twelfth, thirteenth, fourteenth, fifteenth, or sixteenth receivedimaging signal may be normalized by the first received imaging signal.

FIG. 2B schematically illustrates simultaneous actuation of theplurality of ultrasonic transducers. The stethoscope device may comprisea transmit (Tx) generator 220. The Tx generator may be a Tx beamformer.The Tx generator may be configured to operate any one of ultrasonictransducers 210A-D to transmit a first, second, third, or fourthtransmitted ultrasonic imaging signal, respectively. The Tx generatormay operate any two or more of the first, second, third, or fourthultrasonic imaging transducers simultaneously. The stethoscope devicemay further comprise an image synthesis module 230. The image synthesismodule may comprise a receive (Rx) beamformer. The Rx beamformer may beconfigured to operate any one of ultrasonic transducers 210A-D toreceive a first, second, third, or fourth received ultrasonic imagingsignal, respectively. The image synthesis module may subject thereceived ultrasonic imaging signals to an ultrasonic imagereconstruction operation. For instance, the image synthesis module maysubject the received ultrasonic imaging signals to a delay and sumoperation. The image synthesis module may subject the receivedultrasonic imaging signals to any ultrasonic image reconstructionoperation. Though shown as operating four ultrasonic imaging transducersin FIG. 2B, the Tx generator may be configured to operate fifth, sixth,seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth,fourteenth, fifteenth, or sixteenth ultrasonic transducers to transmitfifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth,thirteenth, fourteenth, fifteenth, or sixteenth transmitted ultrasonicimaging signals, respectively. The Tx generator may operate any two ormore of the first, second, third, fourth, fifth, sixth, seventh, eighth,ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth ultrasonic imaging transducers simultaneously. Similar, the Rxbeamformer may be configured to operate fifth, sixth, seventh, eighth,ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth ultrasonic transducers to transmit fifth, sixth, seventh,eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth,fifteenth, or sixteenth transmitted ultrasonic imaging signals,respectively.

The Tx generator may be configured to operate any one of the first,second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthultrasonic transducers to transmit in sequence. FIG. 3 shows operationof the ultrasonic transducers in sequence. As depicted in FIG. 3, anultrasonic transducer that is transmitting a transmitted ultrasonicsignal at a given time is indicated by a solid box. An ultrasonictransducer that is not transmitting at a given time is indicated by adashed box.

FIG. 3A schematically illustrates actuation of a first ultrasonictransducer of the plurality of ultrasonic transducers at a first timepoint. During the first point in time, ultrasonic imaging transducer210A may transmit a first transmitted ultrasonic imaging signal. Duringthe first point in time, ultrasonic imaging transducers 210B, 210C, and210D may not transmit. During the first point in time, ultrasonicimaging transducers 210B, 210C, and 210D may be operated in a receivemode, so as to receive second, third, and fourth received ultrasonicimaging signals, respectively.

FIG. 3B schematically illustrates actuation of a second ultrasonictransducer of the plurality of ultrasonic transducers at a second timepoint. The second point in time may be different from the first point intime. During the second point in time, ultrasonic imaging transducer210B may transmit a second transmitted ultrasonic imaging signal. Duringthe second point in time, ultrasonic imaging transducers 210A, 210C, and210D may not transmit. During the second point in time, ultrasonicimaging transducers 210A, 210C, and 210D may be operated in a receivemode, so as to receive first, second, and fourth received ultrasonicimaging signals, respectively.

FIG. 3C schematically illustrates actuation of a third ultrasonictransducer of the plurality of ultrasonic transducers at a third timepoint. The third point in time may be different from the first point intime and the second point in time. During the third point in time,ultrasonic imaging transducer 210C may transmit a third transmittedultrasonic imaging signal. During the third point in time, ultrasonicimaging transducers 210A, 210B, and 210D may not transmit. During thethird point in time, ultrasonic imaging transducers 210A, 210B, and 210Dmay be operated in a receive mode, so as to receive first, second, andfourth received ultrasonic imaging signals, respectively.

FIG. 3D schematically illustrates actuation of a fourth ultrasonictransducer of the plurality of ultrasonic transducers at a fourth timepoint. The fourth point in time may be different from the first point intime, the second point in time, and the third point in time. During thefourth point in time, ultrasonic imaging transducer 210D may transmit afourth transmitted ultrasonic imaging signal. During the fourth point intime, ultrasonic imaging transducers 210A, 210B, and 210C may nottransmit. During the fourth point in time, ultrasonic imagingtransducers 210A, 210B, and 210C may be operated in a receive mode, soas to receive first, second, and third received ultrasonic imagingsignals, respectively.

The ultrasonic imaging transducers may be operated in any order. Forinstance, any one of ultrasonic imaging transducers 210B, 210C, and 210Dmay be operated in a transmit mode at the first point in time while theother ultrasonic imaging transducers are operated in a receive mode atthe first point in time. Any one of ultrasonic imaging transducers 210A,210C, and 210D may be operated in a transmit mode at the second point intime while the other ultrasonic imaging transducers are operated in areceive mode at the second point in time. Any one of ultrasonic imagingtransducers 210A, 210B, and 210D may be operated in a transmit mode atthe third point in time while the other ultrasonic imaging transducersare operated in a receive mode at the third point in time. Any one ofultrasonic imaging transducers 210A, 210B, and 210C may be operated in atransmit mode at the fourth point in time while the other ultrasonicimaging transducers are operated in a receive mode at the fourth pointin time.

Any two of the ultrasonic imaging transducers may be operated in atransmit mode at any given point in time while any other two of theultrasonic imaging transducers are operated in a receive mode at thatpoint in time. Any three of the ultrasonic imaging transducers may beoperated in a transmit mode at any given point in time while the otherultrasonic imaging transduces is operated in a receive mode at thatpoint in time.

FIG. 4 schematically illustrates a method of forming ultrasonic imagesfrom a plurality of ultrasonic transducers. The method may utilizemeasurements from a plurality of ultrasonic imaging sensors. The methodmay utilize single-pixel and multi-pixel image processing techniques. Inthe single-pixel case, an n-th ultrasonic imaging measurement (where nis a positive integer) may be input to a signal processing unit. Thesignal processing unit may apply any ultrasonic signal processingprocedure to the n-th ultrasonic imaging measurement. The signalprocessing unit may output a signal processed measurement to an imageprocessing unit and to a single-pixel feature extraction unit. The imageprocessing unit may apply any ultrasonic image processing procedure. Thesingle-pixel feature extraction unit may apply any ultrasonicsingle-pixel feature extraction procedure. The single-pixel featureextraction unit may output an extracted feature to an operator.

In the multi-pixel case, an m-th and an (m+1)-th (where m and m+1 arepositive integers) ultrasonic imaging measurement may be input to amulti-pixel image synthesis unit and to a multi-pixel feature extractionunit. The image synthesis unit may apply any ultrasonic image synthesisprocedure. The multi-pixel feature extraction unit may apply anyultrasonic multi-pixel feature extraction procedure. The multi-featureextraction unit may output an extracted feature to an operator.

In the multi-pixel case, image processing methods such as 2-dimensionalsmoothing filters, Harr filters, Gaussian filters, and integrators maybe used to improve the recorded image. Furthermore, each pixel may befiltered in the time-domain to accentuate signal features. A single ormultiple Butterworth, Chebyshev, and elliptic filters can be used tosuppress noise and enhance feature extraction.

FIG. 17 illustrates a method 1700 for receiving a stethoscopic audiosignal, simultaneously transmitting first and second ultrasonic imagingsignals, and receiving first and second ultrasonic imaging signals.

In a first operation 1710, a stethoscopic audio signal is received froman object. The stethoscopic audio signal may be received by astethoscope head comprising a mechanical diaphragm, as described herein.

In a second operation 1720, a first transmitted ultrasonic imagingsignal is transmitted to the object at a first frequency. The firsttransmitted ultrasonic imaging signal may be transmitted by a firstultrasonic transducer, as described herein.

In a third operation 1730, a first received ultrasonic imaging signal isreceived from the object. The first received ultrasonic imaging signalmay be received by a first ultrasonic transducer, as described herein.

In a fourth operation 1740, a second transmitted ultrasonic imagingsignal is transmitted to the object at a second frequency. The secondtransmitted ultrasonic imaging signal may be transmitted by a secondultrasonic transducer, as described herein. The second transmittedultrasonic imaging signal may be transmitted simultaneously with thefirst transmitted ultrasonic imaging signal, as described herein.

In a fifth operation 1750, a second received ultrasonic imaging signalis received from the object. The second received ultrasonic imagingsignal may be received by a second ultrasonic transducer, as describedherein. The second received ultrasonic imaging signal may be receivedsimultaneously with the first transmitted ultrasonic imaging signal, asdescribed herein.

The method 1700 may further comprise an operation (not shown in FIG. 17)of detecting a non-stethoscopic, non-ultrasonic signal. Thenon-stethoscopic, non-ultrasonic signal may be detected by anon-stethoscopic, non-ultrasonic sensor, as described herein.

The method 1700 may be implemented by any of the devices describedherein, such as the devices described herein with respect to FIG. 1,FIG. 2, FIG. 3, or FIG. 4.

Many variations, alterations, and adaptations based on the method 1700provided herein are possible. For example, the order of the operationsof the method 1700 may be changed, some of the operations removed, someof the operations duplicated, and additional operations added asappropriate. Some of the operations may be performed in succession. Someof the operations may be performed in parallel. Some of the operationsmay be performed once. Some of the operations may be performed more thanonce. Some of the operations may comprise sub-operations. Some of theoperations may be automated and some of the operations may be manual.

FIG. 5A schematically illustrates a side view of a stethoscope headcomprising a mechanical diaphragm, a plurality of ultrasoundtransducers, and a plurality of non-stethoscopic, non-ultrasonicsensors. The stethoscope device may comprise the mechanical diaphragm200 and plurality of ultrasonic transducers 210A-D described herein.

FIG. 5B schematically illustrates a perspective view of a stethoscopehead comprising a mechanical diaphragm, a plurality of ultrasoundtransducers, and a plurality of non-stethoscopic, non-ultrasonicsensors. In addition to the mechanical diaphragm and the plurality ofultrasonic transducers, the stethoscope head may comprise one or morenon-stethoscopic, non-ultrasonic sensors. The non-stethoscopic,non-ultrasonic sensors may detect one or more non-stethoscopic,non-ultrasonic signals. As shown in FIG. 5B, may comprise a first lightsource 510 and a first photodetector 520. The first light source may bea light emitting diode (LED) or a laser. The laser may be asemiconductor laser, such as a vertical cavity surface emitting laser(VCSEL). The first photodetector may be a photodiode, an avalanchephotodiode, a photodiode array, a spectrometer, a charge coupled device(CCD) camera, a complementary metal oxide semiconductor (CMOS) camera,or any other photodetector.

The first light source and first photodetector may be configured tooperate as a first pulse oximeter. The pulse oximeter may be configuredto operate as a reflectance pulse oximeter. The first light source maydirect light to the subject's skin, such as to the skin of the subject'sfingertip, finger, hand, arm, or any other location on the subject'sskin. The light may be reflected by the subject's skin and detected bythe first light detector. Different wavelengths of light incident on thesubject's skin may be absorbed to different extents. The absorption ofthe different wavelengths may be indicative of the subject's oxygensaturation (spO₂).

The stethoscope head may further comprise a second light source and asecond photodetector. The second light source and second photodetectormay be similar to the first light source and the first photodetector,respectively. The second light source and second photodetector may beconfigured to operate as a second pulse oximeter. The second pulseoximeter may be similar to the first pulse oximeter. In some cases, thefirst light source, first photodetector, the second light source, andthe second photodetector may be configured to operate as a single pulseoximeter. For instance, the first and second light sources may each emitfirst and second monochromatic light, respectively, having differentwavelengths. The first and second photodetectors may measure theabsorbance of the first and second monochromatic light, respectively.The measurements may allow a determination of the subject's spO₂.

The stethoscope head may comprise 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, or more than 16 non-stethoscopic, non-ultrasonicsensors. Each non-stethoscopic, non-ultrasonic sensor may be any one ofa non-stethoscopic audio sensor, a temperature sensor, an optic sensor,an electrical sensor, or an electrochemical sensor. Thenon-stethoscopic, non-ultrasonic sensor may detect a signalcorresponding to a subject's body temperature, a subject's respirationrate, a subject's respiration quality, a subject's respirationpathology, a subject's blood pressure, a subject's blood glucoseconcentration, or a subject's blood oxygenation saturation (spO₂).

FIG. 6A schematically illustrates a top view of a stethoscope headcomprising a body, an impedance matching substrate, and a userinterface. The stethoscope head 110 may comprise the mechanicaldiaphragm and the one or more ultrasonic transducers described herein.The stethoscope head may further comprise an impedance matchingsubstrate 600. The impedance matching substrate may be composed of animpedance matching material. The impedance matching material mayincrease the efficiency with which any one of the first, second, third,fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth,thirteenth, fourteenth, fifteenth, or sixteenth transmitted or receivedultrasonic imaging signals are passed between the correspondingultrasonic transducer and a sample under examination.

FIG. 6B schematically illustrates a side view of a stethoscope headcomprising a body, an impedance matching substrate, and a userinterface. On a top layer, the stethoscope head may comprise theimpedance matching substrate 600.

In a middle layer, the stethoscope head may comprise a body 610. Thebody may comprise a battery. The battery may allow one or more of thecomponents of the stethoscope device described herein to operate withoutaccess to an external power source. The body may comprise a powerconnector. The power connector may be configured to receive electricalpower from an external power source, such as an electrical outlet. Thepower connector may allow one or more of the components of thestethoscope device described herein to operate while powered by anexternal power source. The power connector may allow the battery to becharged, either while one or more of the components described herein arein operation or while the stethoscope device is not in use. The powerconnector may be an inductive power coil.

In a bottom layer, the stethoscope head may comprise a control 620, asdescribed herein.

FIG. 6C schematically illustrates a bottom view of a stethoscope headcomprising a body, an impedance matching substrate, and a userinterface. The control 620 may allow the stethoscope device to beoperated in a variety of modes. For instance, the control may allow thestethoscope device to be operated in a stethoscope mode. The stethoscopemode may allow a user to use the stethoscope device as a traditionalstethoscope, providing the user the ability to listen to soundsassociated with biological processes through the stethoscope while oneor more of the non-stethoscopic sensors (such as the plurality ofultrasonic transducers or any one of the non-stethoscopic,non-ultrasonic sensors) are powered off or operating in a standby mode.The control may allow the stethoscope device to be operated in anultrasonic imaging mode. The ultrasonic imaging mode may allow a user touse the stethoscope device as an ultrasonic imaging device, providingthe user the ability to ultrasonic images of an internal structure of asubject. In the ultrasonic imaging mode, one or more of thenon-stethoscopic, non-ultrasonic sensors may be powered off or operatingin a standby mode. In the ultrasonic imaging mode, all of thenon-stethoscopic, non-ultrasonic sensors may be powered on. The controlmay allow the stethoscope device to be operated in a non-stethoscopic,non-ultrasonic mode. The non-stethoscopic, non-ultrasonic mode may allowa user to use the stethoscope device to obtain any non-stethoscopic,non-ultrasonic sensor data described herein from a subject. In thenon-stethoscopic, non-ultrasonic mode, one or more of the ultrasonictransducers may be powered off or operating in a standby mode. In theultrasonic imaging mode, all of the ultrasonic transducers may bepowered on. The stethoscope device may be operated in a mode in whichmore than one sensor component (such as the mechanical diaphragm, one ormore ultrasonic transducers, and one or more non-stethoscopic,non-ultrasonic sensors) are operated together to obtain stethoscopic,ultrasonic, and non-stethoscopic, non-ultrasonic sensor datasimultaneously or in any possible sequence.

The control may comprise a user interface. The user interface may beconfigured to provide a user with feedback based on one or more of astethoscopic signal, an ultrasonic imaging signal, or anon-stethoscopic, non-ultrasonic signal described herein. The userinterface may comprise a display. The user interface may display one ormore of a stethoscopic signal, an ultrasonic imaging signal, or anon-stethoscopic, non-ultrasonic signal described herein. For instance,the user interface may display a heart rate 630 of a subject that may bedetected by a heart rate sensor described herein. The user interface maydisplay a graph 640 of the subject's heart rate over time. The userdevice may display an ultrasonic image or a representation of anynon-stethoscopic, non-ultrasonic signal obtained by anynon-stethoscopic, non-ultrasonic sensor described herein.

The user interface may comprise a touchscreen device. The touchscreendevice may function as a display, as described herein. The touchscreendevice may also allow a user to direct commands to the stethoscopedevice. For instance, the touchscreen device may allow a user of thestethoscope device to select any one of the operating modes of thestethoscope device described herein.

The stethoscope device may further comprise a networking modality. Thenetworking modality may be a wired networking modality. For instance,the stethoscope device may comprise an Ethernet adaptor or any otherwired networking modality. The networking modality may be a wirelessnetworking modality. The wireless networking modality may comprise aninductive power coil for transmitting and receiving data. Thestethoscope device may comprise a wireless transceiver. For instance,the stethoscope device may comprise a Wi-Fi transceiver such as an802.11a transceiver, 802.11b transceiver, 802.11g transceiver, 802.11ntransceiver, 802.11ac transceiver, 802.11ad transceiver, 802.11aftransceiver, 802.11ah transceiver, 80.211ai transceiver, 802.11ajtransceiver, 802.11aq transceiver, 802.11ax transceiver, 802.11aytransceiver, or any other Wi-Fi transceiver. The wireless networkingmodality may comprise a cellular transceiver such as a code divisionmultiple access (CDMA) transceiver, a global system for mobiles (GSM)transceiver, a third-generation (3G) cellular transceiver, afourth-generation (4G) cellular transceiver, a long-term evolution (LTE)cellular transceiver, a fifth-generation (5G) cellular transceiver, orany other cellular transceiver. The wireless networking modality maycomprise a Bluetooth transceiver. The wireless networking modality maycomprise any other wireless networking modality. The wireless networkingmodality may be configured to communicate one or more of a stethoscopicsignal, a received ultrasonic signal, or a non-stethoscopic,non-ultrasonic signal described herein to a peripheral device. Forinstance, the wireless networking modality may be configured tocommunicate one or more of the signals to a smartphone, smartwatch, orother smart device, a tablet, a laptop, or other computing device, or aserver, such as a cloud-based server.

The stethoscope device may comprise a microphone and a speaker. Themicrophone and speaker may enable communication between a user of thestethoscope device and the stethoscope device itself. The speaker mayallow a user to receive the results of one or more of a stethoscopicmeasurement, an ultrasonic imaging measurement, or a non-stethoscopic,non-ultrasonic measurement via an audio announcement from thestethoscope device. The microphone may allow a user to provide commandsto the stethoscope device orally. The microphone may be coupled to anatural language processing system to parse commands spoken by the userto the stethoscope device.

FIG. 7 schematically illustrates use of a stethoscope head comprising auser interface in an interactive imaging mode. The stethoscope devicemay be used to search for a pulse of a subject. When the stethoscopedevice fails to detect a strong pulse signal, the stethoscope device mayindicate to a user that the stethoscope head should be moved to adifferent location. The display 520 may indicate that a heart rate 530is yet to be determined. The display may comprise an indicator 800 thatthe stethoscope head should be moved in a particular direction. Forinstance, the display may show an arrow pointing in the direction thatthe stethoscope head should be moved.

FIG. 18 illustrates a method 1800 for receiving a stethoscopic audiosignal, transmitting and receiving an ultrasonic imaging signal, anddetecting a non-stethoscopic, non-ultrasonic imaging signal.

In a first operation 1810, a stethoscopic audio signal is received froman object. The stethoscopic audio signal may be received by astethoscope head comprising a mechanical diaphragm, as described herein.

In a second operation 1820, a transmitted ultrasonic imaging signal istransmitted to the object. The transmitted ultrasonic imaging signal maybe transmitted by an ultrasonic transducer, as described herein.

In a third operation 1830, a received ultrasonic imaging signal isreceived from the object. The received ultrasonic imaging signal may bereceived by an ultrasonic transducer, as described herein.

In a fourth operation 1840, a non-stethoscopic, non-ultrasonic signal isdetected. The non-stethoscopic, non-ultrasonic signal may be detected bya non-stethoscopic, non-ultrasonic sensor, as described herein.

The method 1800 may be implemented by any of the devices describedherein, such as the devices described herein with respect to FIG. 5,FIG. 6, or FIG. 7.

Many variations, alterations, and adaptations based on the method 1800provided herein are possible. For example, the order of the operationsof the method 1800 may be changed, some of the operations removed, someof the operations duplicated, and additional operations added asappropriate. Some of the operations may be performed in succession. Someof the operations may be performed in parallel. Some of the operationsmay be performed once. Some of the operations may be performed more thanonce. Some of the operations may comprise sub-operations. Some of theoperations may be automated and some of the operations may be manual.

Any one of the stethoscopic signals, ultrasonic imaging signals, ornon-stethoscopic, non-ultrasonic signals described herein may becorrelated using a model. For instance, the stethoscope device describedherein may correlate a first and second signal. The first signal may bea stethoscopic signal, an ultrasonic imaging signal, or anon-stethoscopic, non-ultrasonic signal. The second signal may be astethoscopic signal, an ultrasonic imaging signal, or anon-stethoscopic, non-ultrasonic signal. The first and second signalsmay be correlated to generate one or more extracted feature parameters.Third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh,twelfth, thirteenth, fourteenth, fifteenth, or sixteenth signals mayeach be a stethoscopic signal, an ultrasonic imaging signal, or anon-stethoscopic, non-ultrasonic signal and may be further correlatedwith the first and second signals to generate one or more extractedfeature parameters. The extracted feature parameters may be indicativeof one or more physiological parameters, such as a heart rate, bloodpressure, blood oxygenation, or any other physiological parameterdescribed herein.

The model may correlate the first and second signals by first convolvingeach of the first and second signals with a weighting function. Thefirst signal may be convolved by a first weighting function to form afirst weighted signal. The second signal may be convolved by a secondweighting function to form a second weighted signal. The first andsecond weighted signals may then be correlated (such as byauto-correlation or cross-correlation) to generate the extracted featureparameters. The model may convolve third, fourth, fifth, sixth, seventh,eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth,fifteenth, or sixteenth signals with third, fourth, fifth, sixth,seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth,fourteenth, fifteenth, or sixteenth weighting functions, respectively,to form third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthweighted signals, respectively. The third, fourth, fifth, sixth,seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth,fourteenth, fifteenth, or sixteenth weighted signals may be correlatedwith the first and second weighted signals to generate the extractedfeature parameters.

The model may correlate the first and second signals by applying amathematical transformation to each of the first and second signals. Forinstance, each of the first and second imaging signals may betransformed by a Fourier transform, a Fourier integral transform, aFourier series transform, a Z-transform, a wavelet transform, a cosineseries transform, a sine series transform, a Taylor series transform, aLaurent series transform, a Laplace transform, a Hadamard transform, orany other mathematical transform. The first signal may be transformed bya first mathematical transform to form a first transformed signal. Thesecond signal may be transformed by a second mathematical transform toform a second transformed signal. The first and second transformedsignals may then be correlated (such as by auto-correlation orcross-correlation) to generate the extracted feature parameters. Themodel may transform third, fourth, fifth, sixth, seventh, eighth, ninth,tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth signals with third, fourth, fifth, sixth, seventh, eighth,ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth mathematical transforms, respectively, to form third, fourth,fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth,thirteenth, fourteenth, fifteenth, or sixteenth transformed signals,respectively. The third, fourth, fifth, sixth, seventh, eighth, ninth,tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, orsixteenth transformed signals may be correlated with the first andsecond transformed signals to generate the extracted feature parameters.

The model may correlate the first and second signals by encoding andmapping the first and second signals to a set of extracted featuresusing a machine learning technique. The model may correlate third,fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth,thirteenth, fourteenth, fifteenth, or sixteenth signals with the firstand second transformed signals by encoding and mapping the first,second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth,eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenthsignals to a set of extracted features using a machine learningtechnique. The model may correlate any number of transformed signals.

FIG. 8 illustrates a schematic block diagram of a machine learningsystem comprising a pre-processing module and a machine learning module.The machine learning system 800 may comprise a pre-processing module 810and a machine learning module (also referred to as an approximator or anapproximation module) 820. The components within the machine learningsystem may be operatively connected to one another via a network or anytype of communication link that allows transmission of data from onecomponent to another. The machine learning system may be implementedusing software, hardware, or a combination of software and hardware inone or more of the components of the systems and methods describedherein.

Physiological information 802 may be collected using one or more of themechanical diaphragm, ultrasonic imaging transducers, ornon-stethoscopic, non-ultrasonic sensors of the stethoscope devicedescribed herein. The pre-processing module 810 may be configured tosubject the physiological information to pre-processing. Thepre-processing module may remove artifacts produced, for instance, bythe mechanical diaphragm, ultrasonic imaging transducers, ornon-stethoscopic, non-ultrasonic sensors. The pre-processing module maycorrect the microscope images for mechanical noise, such as movement ofthe stethoscope device. The pre-processing module may correct fornon-uniform detection sensitivities of the ultrasonic transducers. Thepre-processing module may apply smoothing filters to reduce sensor noisefrom any one of the mechanical diaphragm, ultrasonic imagingtransducers, or non-stethoscopic, non-ultrasonic sensors. Thepre-processing module may apply any noise reduction or signalenhancement methods to increase the signal-to-noise ration of anysignals obtained by the mechanical diaphragm, ultrasonic imagingtransducers, or non-stethoscopic, non-ultrasonic sensors. Thepre-processing module may be configured to output pre-processedphysiological information 804.

The machine learning module 820 may be configured to process thepre-processed physiological information 804 to extract a meaningfulrepresentation of the physiological information. For example, themachine learning module may generate a set of minimal physiological data106 from the pre-processed physiological information. The minimalphysiological data may correspond to a highly compressed meaningfulrepresentation of a stream of physiological information. The minimalphysiological data may correspond to one or more clinically relevantfeature parameters described herein, such as a body temperature, arespiration rate, a respiration quality, a respiration pathology, ablood pressure, a blood glucose concentration, a blood gasconcentration, a blood oxygenation saturation (spO₂), or any otherclinically relevant feature parameters.

In the machine learning module, a new representation for thephysiological data may be found where the new representation hascharacteristics such as low dimensionality, sparse coding, and/orinvariance to certain noise or signal transformations. For example, theapproximator may find representations that are insensitive (or lesssensitive) to signal transformations that occur when the stethoscopedevice moves relative to signal sources, such as due to mild mechanicaldisturbance. The machine learning module may account for changes in thesensor responses over time, for instance due to aging of components inthe stethoscope device, fluctuations in transmitted ultrasonic powerdelivered to the sample, and other phenomena which alter the signalsdetected by the stethoscope device over time. In each of the abovecases, one or more deterministic transformations may be applied to thephysiological data, and depending on the representational schemeselected by the approximator, these transformations may or may notresult in a change in the output of the machine learning system. Bytraining the approximator to respond invariantly in the face ofpredictable and deterministic perturbations to its input, theselow-level changes may be made invisible to the high-level output of themachine learning system.

The above objectives may be achieved by applying one or more machinelearning methods that decompose their input according to a self-learned(unsupervised) set of bases, while incorporating certain constraints orpriors in said decomposition. Some of the constraints used may includeconstraints which are aware of facts about the underlying physiologicalstate space.

The machine learning module may also be implemented by explicitlymodeling the data stream using probabilistic graphic models and usingmatrix methods such as L1/L2 lasso regularization (for finding sparsesolutions) or eigenvector based approaches to find low rankapproximations of the matrix. The machine learning module may also beimplemented using neural networks such as autoencoders, stackedautoencoders, denoising autoencoders, deep belief networks, etc.

The approximation stage may be implemented as a multi-layered neuralnetwork where the output of each hidden layer of a plurality of hiddenlayers attempts to reconstruct the input from the preceding layer withsome constraint imposed or where its input has been either corrupted ortransformed in a way to favor invariant representation. This may includeso-called “deep belief networks” or “stacked auto-encoders”. The innerlayers may be constrained by means of limiting what values their weightsmay take, or by limiting how quickly or tightly their weights may settletowards the optimum as a form of a regularization strategy, etc. Themultiple inner layers may lead to increasing degrees of abstraction andinvariance to small perturbations of the signal. The layers may beupdated separately, allowing for changes in physiological informationover time to be learned by retraining of a low-level layer while theoutput of the higher level layers remain the same.

The training phase to determine the parameters for the algorithmimplemented at this stage may occur offline, but use of the approximatormay be in real time. Updating of weights/coefficients may then occurregularly and while the approximator is in use.

FIG. 9 illustrates an exemplary multi-layer autoencoder configured toconvert a set of pre-processed physiological information from thepre-processing module into minimal physiological data, in accordancewith some embodiments. The machine learning module 820 may comprise anencoder 830 and a decoder 850. The machine learning module may beconfigured to output minimal physiological data 840. The minimalphysiological data may correspond to the inner-most layer of theautoencoder.

In some embodiments, the encoder may further comprise a plurality ofencoding layers. Each encoding layer may comprise a plurality of nodesbearing a plurality of numerical weights. Similarly, the decoder mayfurther comprise a plurality of decoding layers. Each decoding layer maycomprise a plurality of nodes bearing a plurality of numerical weights.The innermost layer of the machine learning module may be the minimalphysiological data. The minimal physiological data may comprise aplurality of nodes bearing numerical weights. The minimal physiologicaldata may specify an abstract yet meaningful representation ofphysiological information within the machine learning architectureshown. In some embodiments, the machine learning module may comprise anautoencoder, such that the output of the decoder is identical to andprovided as the input to the encoder. In some embodiments, theautoencoder may be a multi-layer autoencoder.

The encoder may be configured to receive an input comprising the set ofpre-processed physiological information 804 from the pre-processingmodule. The set of pre-processed physiological information may bearranged as a vector S. The first layer of the encoder may be configuredto reduce the dimensionality of the set of pre-processed physiologicalinformation by applying a transformation to the vector S. In someembodiments, the transformation may be a linear transformation. In otherembodiments, the transformation may be a nonlinear transformation. Thetransformation may produce an output vector T having reduceddimensionality relative to the vector S, based on a function o, a matrixW of weights at each node in the layer, and another vector b:

T=a(WS+b)  (Equation 1)

The vector T may then be input to the second layer. Each successiveencoding layer may apply matrix transformations of the same form asEquation (1), with a successive reduction in dimensionality at eachlayer until the innermost layer (the minimal physiological data) isreached.

The decoder may be configured to undo the abovementioned reduction indimensionality in order to calculate the accuracy of the matrices ofweights applied at each layer of the encoder. The minimal physiologicaldata may be input to the first layer of the decoder, which may apply alinear transformation to increase dimensionality. Each successivedecoding layer may apply further matrix transformations, until an outputS′ from the encoding layer of the same dimensionality as the originalinput set S is reached.

The initial weights of each node in each layer of the encoder, decoder,and minimal physiological data may be selected based on anypredetermined procedure. The series of matrix transformations may beapplied to map the input S at the first encoding layer to the output S′at the final decoding layer. An error function, such as an L1 error oran L2 error, may be calculated from S and S′. An algorithm, such asbackpropagation, may then be applied to update the weights at each nodein each layer of the encoder, decoder, and minimal physiological data.The algorithm may be applied iteratively until the error functionassessed at the output of the decoder reaches a minimum value.

In some embodiments, sparsity restraints may be applied on some or allof the layers in the machine learning module.

The machine learning module may be configured to distill a datasethaving high dimensionality into a minimal set of numerical values thatstill maintains the essential features of the dataset withoutredundancy. This set of numerical values then forms the minimalphysiological data corresponding to a given set of physiologicalinformation.

In some embodiments, the autoencoder can be designed in multiple layersin order to improve its robustness against changes in the stethoscopesystem. This may also allow specific layers to be retrained in isolationto reduce the computational overhead of adapting the system to changingrecording conditions (e.g., physical changes to or variations in sensorsof the stethoscope system).

Accordingly, the machine learning system described herein may serve as apipeline for processing physiological data comprising information fromnumerous physiological processes. The system may transform the imagedata to a higher-level symbol stream which represents salient featuresof the physiological data.

FIG. 10 illustrates a flowchart representing a process by which minimalphysiological data may be extracted from the input to an autoencoder, inaccordance with some embodiments. The encoder 830 (of FIG. 9) may acceptas input a vectorized set of pre-processed physiological information 804from the pre-processing module 810 (see FIG. 8). The initial weights1002 of each node in each layer of the encoder 830, minimalphysiological data 840, and decoder 850 may be selected according to anypreferred procedure. The encoder may apply a set of lineartransformations 1004, one linear transformation at each encoding layer,to calculate a first-pass linear minimal physiological data 840. Eachlinear transformation at each layer of the encoder may reduce thedimensionality of the information passed to the next layer of theencoder.

The decoder may apply a further set of linear transformations 1006, onelinear transformation at each decoding layer. Each linear transformationat each layer of the decoder may increase the dimensionality of theinformation passed to the next layer of the decoder. The final layer ofthe decoder may produce a test code given by the weights of the nodes ofthe final layer of the decoder. The test code may be of the samedimensionality as the input to the decoder.

The values of the test code and the values of the input to the encodermay be compared through an error function in order to calculate anerror. The error function may be the L1 error, given by the sum ofabsolute differences between the test code and the input to the encoder.The error function may be the L2 error or the Euclidean error, given bythe sum of the squared differences between the test code and the inputto the encoder. The error function may be an LN error, or a generalizedEuclidean error of arbitrary dimensionality N. The error function may beany other error function. The error function may be the same for eachiteration. The error function may change between successive iterations.

The error calculated from the test code and the input to the encoder maybe compared to a condition. The condition may be based on apredetermined threshold. If the error satisfies the condition, theminimal physiological data may be accepted 1014 and the value of theminimal physiological data may be output 806. If the error fails tosatisfy the condition, the weights of each node in each layer of theencoder 830, physiological data 840, and decoder 850 may be updated 1014according to any preferred procedure. At this point, the procedure mayproceed iteratively until the condition is satisfied. The condition maybe defined such that that the error is smaller than a predeterminedthreshold value. The condition may also be defined such that the erroris the smaller than any one of previously calculated errors. In someembodiments, the condition may remain the same for each iteration. Inother embodiments, the condition may change between successiveiterations. The procedure and iterations may be configured to end whenthe condition is met. In some embodiments, when the condition is met,the physiological population data from the current iteration will beoutput.

Although particular reference is made to autoencoding methods, othermachine learning techniques including various supervised machinelearning techniques, various semi-supervised machine learningtechniques, and/or various unsupervised machine learning techniques maybe implemented in the in the machine learning module. The machinelearning techniques may be trainable. The machine learning techniquesmay be trainable by interaction with a human trainer (supervised machinelearning), by self-training (unsupervised machine learning), or by acombination of the two (semi-supervised machine learning). For instance,the machine learning module may utilize alternating decision trees(ADTree), Decision Stumps, functional trees (FT), logistic model trees(LMT), logistic regression, Random Forests, linear classifiers, neuralnetworks, sparse dictionaries, Diabolo networks, or any machine learningalgorithm or statistical algorithm known in the art. One or morealgorithms may be used together to generate an ensemble method, whereinthe ensemble method may be optimized using a machine learning ensemblemeta-algorithm such as a boosting (e.g., AdaBoost, LPBoost, TotalBoost,BrownBoost, MadaBoost, LogitBoost, etc.) to reduce bias and/or variance.Machine learning analyses may be performed using one or more of manyprogramming languages and platforms known in the art, such as R, Weka,Python, and/or Matlab, for example.

FIG. 11 schematically illustrates a method for extracting features froma stethoscopic audio signal obtained by a mechanical diaphragm, anultrasonic signal obtained by an ultrasonic transducer, and one or morenon-stethoscopic, non-ultrasonic signals obtained by a non-stethoscopic,non-ultrasonic sensor. The method may utilize any one of the techniquesdescribed herein with respect to FIG. 8, FIG. 9, and FIG. 10 to apply anencoder and decoder to a series of sensor data. The sensor data maycomprise a time series of sensor values f1(t) associated with astethoscope sensor (such as the mechanical diaphragm described herein),a time series of sensor values f2(t) associated with a first ultrasoundsensor, a time series of sensor values f3(t) associated with a firstphotodiode, and so on. In general, the sensor data may comprise n timeseries of sensor values, where n is a positive integer. Each time seriesof sensor values may be associated with any one of the stethoscope,ultrasonic, or non-stethoscopic, non-ultrasonic sensors describedherein. Each time series may be passed to an autoencoder, progressthrough a correlator (also referred to as a set of inner layers) and adecoder, and output extracted features. For instance, the autoencoder,correlator, and decoder may output extracted features related to a heartrate, blood pressure, blood oxygenation, or any other clinicallyrelevant feature described herein.

FIG. 19 illustrates a method 1900 for receiving a stethoscopic audiosignal, transmitting and receiving an ultrasonic imaging signal, andcorrelating the stethoscopic audio signal and the ultrasonic imagingsignal.

In a first operation 1910, a stethoscopic audio signal is received froman object. The stethoscopic audio signal may be received by astethoscope head comprising a mechanical diaphragm, as described herein.

In a second operation 1920, a transmitted ultrasonic imaging signal istransmitted to the object. The transmitted ultrasonic imaging signal maybe transmitted by an ultrasonic transducer, as described herein.

In a third operation 1930, a received ultrasonic imaging signal isreceived from the object. The received ultrasonic imaging signal may bereceived by an ultrasonic transducer, as described herein.

In a fourth operation 1940, the stethoscopic audio signal and thereceived ultrasonic imaging signal are correlated. The stethoscopicaudio signal and the received ultrasonic imaging signal may becorrelated by a model, as described herein.

The method 1900 may further comprise an operation (not shown in FIG. 19)of detecting a non-stethoscopic, non-ultrasonic signal. Thenon-stethoscopic, non-ultrasonic signal may be detected by anon-stethoscopic, non-ultrasonic sensor, as described herein.

The method 1900 may be implemented by any of the devices describedherein, such as the devices described herein with respect to FIG. 8,FIG. 9, FIG. 10, or FIG. 11.

Many variations, alterations, and adaptations based on the method 1900provided herein are possible. For example, the order of the operationsof the method 1900 may be changed, some of the operations removed, someof the operations duplicated, and additional operations added asappropriate. Some of the operations may be performed in succession. Someof the operations may be performed in parallel. Some of the operationsmay be performed once. Some of the operations may be performed more thanonce. Some of the operations may comprise sub-operations. Some of theoperations may be automated and some of the operations may be manual.

The stethoscope device described herein may be configured to performbeamsteering of a transmitted ultrasonic imaging signal by interfering atransmitted ultrasonic imaging signal with an audio signal. Thestethoscope head may comprise an audio transducer for transmitting anaudio signal to a subject. The stethoscope head may comprise aninterference circuit for interfering a transmitted ultrasonic imagingsignal with the audio signal. The interference circuit may steer theultrasonic imaging signal to an object. The audio transducer orinterference circuit may be detachably coupled to a housing of thestethoscope head. The audio transducer or interference circuit may bephysically coupled to a housing of the stethoscope head. The audiotransducer or interference circuit may be functionally coupled to ahousing of the stethoscope head.

The interference circuit may interfere the transmitted ultrasonicimaging signal with the audio signal based on a model of the object'sresponse to the audio signal. The model may be similar to any modeldescribed herein. The model may correlate the ultrasonic imaging signalwith the audio signal to generate an extracted feature parameter. Themodel may correlate the ultrasonic signal with the audio signal byconvolving the ultrasonic and audio signals with first and secondweighting functions, respectively, to form weighted ultrasonic andweighted audio signals, respectively. The weighted ultrasonic andweighted audio signals may be correlated by performing auto-correlationor cross-correlation on the weighted signals. The model may correlatethe ultrasonic signal with the audio signal by transforming (as by anintegral Fourier transform, Fourier series transform, Z-transform,wavelet transform, cosine series transform, sine series transform,Taylor series transform, Laurent series transform, Laplace transform,Hadamard transform, or any other mathematical transform) the ultrasonicand audio signals to form transformed ultrasonic and transformed audiosignals, respectively. The transformed ultrasonic and transformed audiosignals may be correlated by performing auto-correlation orcross-correlation on the transformed signals. The model may correlatedthe ultrasonic signal and audio signal by encoding and mapping theultrasonic and audio signals to a set of features using a machinelearning technique. The machine learning technique may be a neuralnetwork, sparse dictionary, Diabolo network, or any other machinelearning technique described herein.

FIG. 20 illustrates a method 2000 for receiving a stethoscopic audiosignal, transmitting and receiving an ultrasonic imaging signal,transmitting an audio signal, and interfering the transmitted ultrasonicimaging signal and the audio signal to steer the ultrasonic imagingsignal.

In a first operation 2010, a stethoscopic audio signal is received froman object. The stethoscopic audio signal may be received by astethoscope head comprising a mechanical diaphragm, as described herein.

In a second operation 2020, a transmitted ultrasonic imaging signal istransmitted to the object. The transmitted ultrasonic imaging signal maybe transmitted by an ultrasonic transducer, as described herein.

In a third operation 2030, a received ultrasonic imaging signal isreceived from the object. The received ultrasonic imaging signal may bereceived by an ultrasonic transducer, as described herein.

In a fourth operation 2040, an audio signal is transmitted to theobject. The audio signal may be transmitted by an audio transducer, asdescribed herein.

In a fifth operation 2050, transmitted ultrasonic imaging signal isinterfered with the audio signal to steer the ultrasonic imaging signal.The transmitted ultrasonic imaging signal and the audio signal may beinterfered by an interference circuit, as described herein.

The method 2000 may further comprise an operation (not shown in FIG. 20)of detecting a non-stethoscopic, non-ultrasonic signal. Thenon-stethoscopic, non-ultrasonic signal may be detected by anon-stethoscopic, non-ultrasonic sensor, as described herein.

The method 2000 may be implemented by any of the devices describedherein.

Many variations, alterations, and adaptations based on the method 2000provided herein are possible. For example, the order of the operationsof the method 2000 may be changed, some of the operations removed, someof the operations duplicated, and additional operations added asappropriate. Some of the operations may be performed in succession. Someof the operations may be performed in parallel. Some of the operationsmay be performed once. Some of the operations may be performed more thanonce. Some of the operations may comprise sub-operations. Some of theoperations may be automated and some of the operations may be manual.

FIG. 12 shows how information from the stethoscope device 100 may betransmitted to information systems. As described herein, the stethoscopedevice may have the ability to transmit or receive information. Thestethoscope device may transmit information, such as the sensor data orextracted features, to a variety of information systems. The informationmay be transmitted to an external display for easy visualization, storedin an institutional database (such as a database associated with adoctor's office, hospital, or network of offices or hospitals), or to acloud-based health system. The information may thus be accessed byinstitutions that have an interest in the information.

FIG. 13 shows how information from the stethoscope device 100 may beutilized by different individuals or institutions. The information fromthe stethoscope device may be transmitted to a cloud server. The cloudserver may apply algorithms to the information. The information may bestored in a Health Insurance Portability and Accountability (HIPAA)Act-compliant database. The information may be accessed by a nurse, aphysician (such as a consulting physician), an emergency medicaltechnician, or another medical professional. The information may beaccessed by a parent of a patient, for instance.

Digital Processing Device

The systems, apparatus, and methods described herein may include adigital processing device, or use of the same. The digital processingdevice may include one or more hardware central processing units (CPU)that carry out the device's functions. The digital processing device mayfurther comprise an operating system configured to perform executableinstructions. In some instances, the digital processing device isoptionally connected to a computer network, is optionally connected tothe Internet such that it accesses the World Wide Web, or is optionallyconnected to a cloud computing infrastructure. In other instances, thedigital processing device is optionally connected to an intranet. Inother instances, the digital processing device is optionally connectedto a data storage device.

In accordance with the description herein, suitable digital processingdevices may include, by way of non-limiting examples, server computers,desktop computers, laptop computers, notebook computers, sub-notebookcomputers, netbook computers, netpad computers, set-top computers, mediastreaming devices, handheld computers, Internet appliances, mobilesmartphones, tablet computers, personal digital assistants, video gameconsoles, and vehicles. Those of skill in the art will recognize thatmany smartphones are suitable for use in the system described herein.Those of skill in the art will also recognize that select televisions,video players, and digital music players with optional computer networkconnectivity are suitable for use in the system described herein.Suitable tablet computers may include those with booklet, slate, andconvertible configurations, known to those of skill in the art.

The digital processing device may include an operating system configuredto perform executable instructions. The operating system may be, forexample, software, including programs and data, which may manage thedevice's hardware and provides services for execution of applications.Those of skill in the art will recognize that suitable server operatingsystems may include, by way of non-limiting examples, FreeBSD, OpenBSD,NetBSD®, Linux, Apple® Mac OS X Server®, Oracle® Solaris®, WindowsServer®, and Novell® NetWare®. Those of skill in the art will recognizethat suitable personal computer operating systems include, by way ofnon-limiting examples, Microsoft® Windows®, Apple® Mac OS X®, UNIX®, andUNIX-like operating systems such as GNU/Linux. In some cases, theoperating system is provided by cloud computing. Those of skill in theart will also recognize that suitable mobile smart phone operatingsystems include, by way of non-limiting examples, Nokia® Symbian® OS,Apple® iOS®, Research In Motion® BlackBerry OS®, Google® Android®,Microsoft® Windows Phone® OS, Microsoft® Windows Mobile® OS, Linux®, andPalm® WebOS®. Those of skill in the art will also recognize thatsuitable media streaming device operating systems include, by way ofnon-limiting examples, Apple TV®, Roku®, Boxee®, Google TV®, GoogleChromecast®, Amazon Fire®, and Samsung® HomeSync®. Those of skill in theart will also recognize that suitable video game console operatingsystems include, by way of non-limiting examples, Sony® PS3®, Sony®PS4®, Microsoft® Xbox 360®, Microsoft Xbox One, Nintendo® Wii Nintendo®Wii U®, and Ouya®.

In some instances, the device may include a storage and/or memorydevice. The storage and/or memory device may be one or more physicalapparatuses used to store data or programs on a temporary or permanentbasis. In some instances, the device is volatile memory and requirespower to maintain stored information. In other instances, the device isnon-volatile memory and retains stored information when the digitalprocessing device is not powered. In still other instances, thenon-volatile memory comprises flash memory. The non-volatile memory maycomprise dynamic random-access memory (DRAM). The non-volatile memorymay comprise ferroelectric random access memory (FRAM). The non-volatilememory may comprise phase-change random access memory (PRAM). The devicemay be a storage device including, by way of non-limiting examples,CD-ROMs, DVDs, flash memory devices, magnetic disk drives, magnetictapes drives, optical disk drives, and cloud computing based storage.The storage and/or memory device may also be a combination of devicessuch as those disclosed herein.

The digital processing device may include a display to send visualinformation to a user. The display may be a cathode ray tube (CRT). Thedisplay may be a liquid crystal display (LCD). Alternatively, thedisplay may be a thin film transistor liquid crystal display (TFT-LCD).The display may further be an organic light emitting diode (OLED)display. In various cases, on OLED display is a passive-matrix OLED(PMOLED) or active-matrix OLED (AMOLED) display. The display may be aplasma display. The display may be a video projector. The display may bea combination of devices such as those disclosed herein.

The digital processing device may also include an input device toreceive information from a user. For example, the input device may be akeyboard. The input device may be a pointing device including, by way ofnon-limiting examples, a mouse, trackball, track pad, joystick, gamecontroller, or stylus. The input device may be a touch screen or amulti-touch screen. The input device may be a microphone to capturevoice or other sound input. The input device may be a video camera orother sensor to capture motion or visual input. Alternatively, the inputdevice may be a Kinect™, Leap Motion™, or the like. In further aspects,the input device may be a combination of devices such as those disclosedherein.

Non-Transitory Computer Readable Storage Medium

In some instances, the systems, apparatus, and methods disclosed hereinmay include one or more non-transitory computer readable storage mediaencoded with a program including instructions executable by theoperating system of an optionally networked digital processing device.In further instances, a computer readable storage medium is a tangiblecomponent of a digital processing device. In still further instances, acomputer readable storage medium is optionally removable from a digitalprocessing device. A computer readable storage medium may include, byway of non-limiting examples, CD-ROMs, DVDs, flash memory devices, solidstate memory, magnetic disk drives, magnetic tape drives, optical diskdrives, cloud computing systems and services, and the like. In somecases, the program and instructions are permanently, substantiallypermanently, semi-permanently, or non-transitorily encoded on the media.

Computer Program

The systems, apparatus, and methods disclosed herein may include atleast one computer program, or use of the same. A computer programincludes a sequence of instructions, executable in the digitalprocessing device's CPU, written to perform a specified task. In someembodiments, computer readable instructions are implemented as programmodules, such as functions, objects, Application Programming Interfaces(APIs), data structures, and the like, that perform particular tasks orimplement particular abstract data types. In light of the disclosureprovided herein, those of skill in the art will recognize that acomputer program, in certain embodiments, is written in various versionsof various languages.

The functionality of the computer readable instructions may be combinedor distributed as desired in various environments. A computer programmay comprise one sequence of instructions. A computer program maycomprise a plurality of sequences of instructions. In some instances, acomputer program is provided from one location. In other instances, acomputer program is provided from a plurality of locations. Inadditional cases, a computer program includes one or more softwaremodules. Sometimes, a computer program may include, in part or in whole,one or more web applications, one or more mobile applications, one ormore standalone applications, one or more web browser plug-ins,extensions, add-ins, or add-ons, or combinations thereof.

Web Application

A computer program may include a web application. In light of thedisclosure provided herein, those of skill in the art will recognizethat a web application, in various aspects, utilizes one or moresoftware frameworks and one or more database systems. In some cases, aweb application is created upon a software framework such as Microsoft®.NET or Ruby on Rails (RoR). In some cases, a web application utilizesone or more database systems including, by way of non-limiting examples,relational, non-relational, object oriented, associative, and XMLdatabase systems. Sometimes, suitable relational database systems mayinclude, by way of non-limiting examples, Microsoft® SQL Server, mySQL™,and Oracle®. Those of skill in the art will also recognize that a webapplication, in various instances, is written in one or more versions ofone or more languages. A web application may be written in one or moremarkup languages, presentation definition languages, client-sidescripting languages, server-side coding languages, database querylanguages, or combinations thereof. A web application may be written tosome extent in a markup language such as Hypertext Markup Language(HTML), Extensible Hypertext Markup Language (XHTML), or eXtensibleMarkup Language (XML). In some embodiments, a web application is writtento some extent in a presentation definition language such as CascadingStyle Sheets (CSS). A web application may be written to some extent in aclient-side scripting language such as Asynchronous Javascript and XML(AJAX), Flash® Actionscript, Javascript, or Silverlight®. A webapplication may be written to some extent in a server-side codinglanguage such as Active Server Pages (ASP), ColdFusion®, Perl, Java™,JavaServer Pages (JSP), Hypertext Preprocessor (PHP), Python™, Ruby,Tcl, Smalltalk, WebDNA®, or Groovy. Sometimes, a web application may bewritten to some extent in a database query language such as StructuredQuery Language (SQL). Other times, a web application may integrateenterprise server products such as IBM® Lotus Domino®. In someinstances, a web application includes a media player element. In variousfurther instances, a media player element utilizes one or more of manysuitable multimedia technologies including, by way of non-limitingexamples, Adobe® Flash®, HTML 5, Apple® QuickTime®, Microsoft®Silverlight®, Java™, and Unity®.

Mobile Application

A computer program may include a mobile application provided to a mobiledigital processing device. In some cases, the mobile application isprovided to a mobile digital processing device at the time it ismanufactured. In other cases, the mobile application is provided to amobile digital processing device via the computer network describedherein.

In view of the disclosure provided herein, a mobile application iscreated by techniques known to those of skill in the art using hardware,languages, and development environments known to the art. Those of skillin the art will recognize that mobile applications are written inseveral languages. Suitable programming languages include, by way ofnon-limiting examples, C, C++, C#, Objective-C, Java™, Javascript,Pascal, Object Pascal, Python™, Ruby, VB.NET, WML, and XHTML/HTML withor without CSS, or combinations thereof.

Suitable mobile application development environments are available fromseveral sources. Commercially available development environmentsinclude, by way of non-limiting examples, AirplaySDK, alcheMo,Appcelerator®, Celsius, Bedrock, Flash Lite, .NET Compact Framework,Rhomobile, and WorkLight Mobile Platform. Other development environmentsare available without cost including, by way of non-limiting examples,Lazarus, MobiFlex, MoSync, and Phonegap. Also, mobile devicemanufacturers distribute software developer kits including, by way ofnon-limiting examples, iPhone and iPad (iOS) SDK, Android™ SDK,BlackBerry® SDK, BREW SDK, Palm® OS SDK, Symbian SDK, webOS SDK, andWindows® Mobile SDK.

Those of skill in the art will recognize that several commercial forumsare available for distribution of mobile applications including, by wayof non-limiting examples, Apple® App Store, Android™ Market, BlackBerry®App World, App Store for Palm devices, App Catalog for webOS, Windows®Marketplace for Mobile, Ovi Store for Nokia® devices, Samsung® Apps, andNintendo® DSi Shop.

Standalone Application

A computer program may include a standalone application, which is aprogram that is run as an independent computer process, not an add-on toan existing process, e.g., not a plug-in. Those of skill in the art willrecognize that standalone applications are often compiled. A compiler isa computer program(s) that transforms source code written in aprogramming language into binary object code such as assembly languageor machine code. Suitable compiled programming languages include, by wayof non-limiting examples, C, C++, Objective-C, COBOL, Delphi, Eiffel,Java™ Lisp, Python™, Visual Basic, and VB .NET, or combinations thereof.Compilation is often performed, at least in part, to create anexecutable program. A computer program may include one or moreexecutable complied applications.

Web Browser Plug-in

The computer program may include a web browser plug-in. In computing, aplug-in is one or more software components that add specificfunctionality to a larger software application. Makers of softwareapplications support plug-ins to enable third-party developers to createabilities which extend an application, to support easily adding newfeatures, and to reduce the size of an application. When supported,plug-ins enable customizing the functionality of a software application.For example, plug-ins are commonly used in web browsers to play video,generate interactivity, scan for viruses, and display particular filetypes. Those of skill in the art will be familiar with several webbrowser plug-ins including, Adobe® Flash® Player, Microsoft®Silverlight®, and Apple® QuickTime®. In some embodiments, the toolbarcomprises one or more web browser extensions, add-ins, or add-ons. Insome embodiments, the toolbar comprises one or more explorer bars, toolbands, or desk bands.

In view of the disclosure provided herein, those of skill in the artwill recognize that several plug-in frameworks are available that enabledevelopment of plug-ins in various programming languages, including, byway of non-limiting examples, C++, Delphi, Java™ PHP, Python™, and VB.NET, or combinations thereof.

Web browsers (also called Internet browsers) may be softwareapplications, designed for use with network-connected digital processingdevices, for retrieving, presenting, and traversing informationresources on the World Wide Web. Suitable web browsers include, by wayof non-limiting examples, Microsoft® Internet Explorer®, Mozilla®Firefox, Google® Chrome, Apple® Safari®, Opera Software® Opera®, and KDEKonqueror. In some embodiments, the web browser is a mobile web browser.Mobile web browsers (also called mircrobrowsers, mini-browsers, andwireless browsers) are designed for use on mobile digital processingdevices including, by way of non-limiting examples, handheld computers,tablet computers, netbook computers, subnotebook computers, smartphones,music players, personal digital assistants (PDAs), and handheld videogame systems. Suitable mobile web browsers include, by way ofnon-limiting examples, Google® Android® browser, RIM BlackBerry®Browser, Apple® Safari®, Palm® Blazer, Palm® WebOS® Browser, Mozilla®Firefox® for mobile, Microsoft® Internet Explorer® Mobile, Amazon®Kindle® Basic Web, Nokia® Browser, Opera Software® Opera® Mobile, andSony PSP™ browser.

Software Modules

The systems and methods disclosed herein may include software, server,and/or database modules, or use of the same. In view of the disclosureprovided herein, software modules may be created by techniques known tothose of skill in the art using machines, software, and languages knownto the art. The software modules disclosed herein may be implemented ina multitude of ways. A software module may comprise a file, a section ofcode, a programming object, a programming structure, or combinationsthereof. A software module may comprise a plurality of files, aplurality of sections of code, a plurality of programming objects, aplurality of programming structures, or combinations thereof. In variousaspects, the one or more software modules comprise, by way ofnon-limiting examples, a web application, a mobile application, and astandalone application. In some instances, software modules are in onecomputer program or application. In other instances, software modulesare in more than one computer program or application. In some cases,software modules are hosted on one machine. In other cases, softwaremodules are hosted on more than one machine. Sometimes, software modulesmay be hosted on cloud computing platforms. Other times, softwaremodules may be hosted on one or more machines in one location. Inadditional cases, software modules are hosted on one or more machines inmore than one location.

Databases

The methods, apparatus, and systems disclosed herein may include one ormore databases, or use of the same. In view of the disclosure providedherein, those of skill in the art will recognize that many databases aresuitable for storage and retrieval of analytical information describedelsewhere herein. In various aspects described herein, suitabledatabases may include, by way of non-limiting examples, relationaldatabases, non-relational databases, object oriented databases, objectdatabases, entity-relationship model databases, associative databases,and XML databases. A database may be internet-based. A database may beweb-based. A database may be cloud computing-based. Alternatively, adatabase may be based on one or more local computer storage devices.

Services

Methods and systems described herein may further be performed as aservice. For example, a service provider may obtain a sample that acustomer wishes to analyze. The service provider may then encodes thesample to be analyzed by any one of the methods described herein,performs the analysis and provides a report to the customer. Thecustomer may also perform the analysis and provides the results to theservice provider for decoding. In some instances, the service providerthen provides the decoded results to the customer. In other instances,the customer may receive encoded analysis of the samples from theprovider and decodes the results by interacting with softwares installedlocally (at the customer's location) or remotely (e.g. on a serverreachable through a network). Sometimes, the softwares may generate areport and transmit the report to the costumer. Exemplary customersinclude clinical laboratories, hospitals, industrial manufacturers andthe like. Sometimes, a customer or party may be any suitable customer orparty with a need or desire to use the methods provided herein.

Server

The methods provided herein may be processed on a server or a computerserver, as shown in FIG. 14). The server 1401 may include a centralprocessing unit (CPU, also “processor”) 1405 which may be a single coreprocessor, a multi core processor, or plurality of processors forparallel processing. A processor used as part of a control assembly maybe a microprocessor. The server 1401 may also include memory 1410 (e.g.random access memory, read-only memory, flash memory); electronicstorage unit 1415 (e.g. hard disk); communications interface 1420 (e.g.network adaptor) for communicating with one or more other systems; andperipheral devices 1425 which includes cache, other memory, datastorage, and/or electronic display adaptors. The memory 1410, storageunit 1415, interface 1420, and peripheral devices 1425 may be incommunication with the processor 1405 through a communications bus(solid lines), such as a motherboard. The storage unit 1415 may be adata storage unit for storing data. The server 1401 may be operativelycoupled to a computer network (“network”) 1430 with the aid of thecommunications interface 1420. A processor with the aid of additionalhardware may also be operatively coupled to a network. The network 1430may be the Internet, an intranet and/or an extranet, an intranet and/orextranet that is in communication with the Internet, a telecommunicationor data network. The network 1430 with the aid of the server 1401, mayimplement a peer-to-peer network, which may enable devices coupled tothe server 1401 to behave as a client or a server. The server may becapable of transmitting and receiving computer-readable instructions(e.g., device/system operation protocols or parameters) or data (e.g.,sensor measurements, analysis of sensor measurements, etc.) viaelectronic signals transported through the network 1430. Moreover, anetwork may be used, for example, to transmit or receive data across aninternational border.

The server 1401 may be in communication with one or more output devices1435 such as a display or printer, and/or with one or more input devices1440 such as, for example, a keyboard, mouse, or joystick. The displaymay be a touch screen display, in which case it functions as both adisplay device and an input device. Different and/or additional inputdevices may be present such an enunciator, a speaker, or a microphone.The server may use any one of a variety of operating systems, such asfor example, any one of several versions of Windows®, or of MacOS®, orof Unix®, or of Linux®.

The storage unit 1415 may store files or data associated with theoperation of a device, systems or methods described herein.

The server may communicate with one or more remote computer systemsthrough the network 1430. The one or more remote computer systems mayinclude, for example, personal computers, laptops, tablets, telephones,Smart phones, or personal digital assistants.

A control assembly may include a single server 1401. In othersituations, the system may include multiple servers in communicationwith one another through an intranet, extranet and/or the Internet.

The server 1401 may be adapted to store device operation parameters,protocols, methods described herein, and other information of potentialrelevance. Such information may be stored on the storage unit 1415 orthe server 1401 and such data is transmitted through a network.

EXAMPLES

The devices and methods described herein may be used to obtain a varietyof information from a sample. The sample may be a living sample, such asa human or a non-human animal subject, such as non-human primates,horses, livestock such as bovines or sheep, dogs, cats, birds, mice, orany other animal. The systems and methods described herein may be usedto detect or diagnose a variety of health conditions in a human ornon-human subject. For instance, the systems and methods may be used todetect injuries or conditions associated with one or more of the brain,heart, lungs, stomach, small intestine, large intestine, liver, kidney,colon, or any other internal organ of a human or non-human subject. Thesystems and methods may be used to detect injuries or conditionsassociated with one or more of a bone (such as a broken bone),connective tissue (such as a cartilage tear), or blood vessel (such asan aneurysm).

The devices and methods described herein may be utilized to determinethe presence of tumors, fractured bones, ruptured vasculature, laceratedorgans, or free abdominal fluid within a human or non-human subject.Furthermore, the devices and methods may be utilized to identify any ofthe following conditions in a human or non-human subject: venipuncture,central line placement, gallstones, pneumothorax, pleural effusion,pneumonia, cardiac function, pericardial effusion, cardiac tamponade,bladder volume, bowel obstruction, organ structure functionalabnormalities, peritonsillar abscess, superficial or deep space abscess,cellulitis, fluid status, inferior vena cava collapse, carotid intimalthickness, carotid artery dissection, abdominal aortic aneurysm, aorticdissection, and pregnancy.

FIG. 15 depicts the use of an enhanced stethoscope device for monitoringblood pressure. The stethoscope device may be any stethoscope devicedescribed herein. In particular, the stethoscope device may comprise afirst ultrasonic transducer, a light source, and a light detector. Thestethoscope device may optionally comprise a second ultrasonictransducer. The first ultrasonic transducer may operate in a Tx mode.The second ultrasonic transducer may operate in a receive mode. Thestethoscope device may be placed above the skin of a subject (such asskin in a subject's arm). As a bolus of blood travels through an arterybeneath the skin of the subject, the stethoscope device may transmit anultrasonic signal from the first ultrasonic transducer and an opticalsignal from the light source. The ultrasonic signal or the opticalsignal may be scattered, dispersed, or reflected from the bolus. Thescattered, dispersed, or reflected ultrasonic signal or optical signalmay be detector by the second ultrasonic transducer or the lightdetector, respectively. The intensity of the scattered, dispersed, orreflected ultrasonic signal or optical signal may be compared to theintensity of the transmitted ultrasonic signal or the transmittedoptical signal, respectively. These measurements may yield a velocity ofthe blood bolus as measured by the ultrasonic imaging signal and theoptical signal, respectively. The velocity of the blood bolus asmeasured by the ultrasonic imaging signal may be normalized by thevelocity of the blood bolus as measured by the optical signal, or viceversa. These values may be synthesized and correlated to determine oneor more physiometric parameters of the subject, such as the subject'sheart rate, blood pressure, or respiration, as described herein withrespect to FIG. 16.

FIG. 16 illustrates a multi-input multi-output (MIMO) correlation fordetermining a physiometric parameter associated with ultrasonic andoptical measurement of a blood bolus. The MIMO correlation may utilizeany of the modeling techniques described herein, such as any machinelearning or statistical model described herein. The MIMO correlation mayproduce a unique correlation between the ultrasonic imaging signal andthe optical signal. The unique correlation may allow for the extractionof any physiometric information described herein. The MIMO correlationmay allow for the extraction of signals that may otherwise be obfuscatedby noise.

The devices and methods described herein may be utilized forapplications in fields outside of the medical fields described above.For instance, the devices and methods may be used to provide informationabout the internal conditions of mechanical systems, such as the enginesor transmissions of vehicles. The stethoscope functionality may be usedto detect abnormalities in the mechanical processes of an engine ortransmission. The ultrasonic functionality may be used to image theengine or transmission to determine if it has sustained internal damage.The non-stethoscopic, non-ultrasonic sensors may provide additionalinformation about the state of the engine or transmission, such as itstemperature.

The devices and methods may be used for non-destructive testing ofinfrastructure. For instance, the devices and methods may be used toexamine the internal structure of concrete (in streets or highways,bridges, buildings, or other structures) to determine whether theconcrete or metal rebar within the concrete has been damaged. Thedevices and methods may be used to examine the internal structures ofpipelines to determine whether they are damaged and may represent athreat to life, property, or the environment.

The devices and methods described herein may be utilized to examine theinternal structures of other building materials, such as stone, brick,wood, sheetrock, thermal insulating, plastic piping, polyvinyl chloride(PVC) piping, fiberglass, or paint.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. It is not intendedthat the invention be limited by the specific examples provided withinthe specification. While the invention has been described with referenceto the aforementioned specification, the descriptions and illustrationsof the embodiments herein are not meant to be construed in a limitingsense. Numerous variations, changes, and substitutions will now occur tothose skilled in the art without departing from the invention.Furthermore, it shall be understood that all aspects of the inventionare not limited to the specific depictions, configurations or relativeproportions set forth herein which depend upon a variety of conditionsand variables. It should be understood that various alternatives to theembodiments of the invention described herein may be employed inpracticing the invention. It is therefore contemplated that theinvention shall also cover any such alternatives, modifications,variations or equivalents. It is intended that the following claimsdefine the scope of the invention and that methods and structures withinthe scope of these claims and their equivalents be covered thereby.

1.-23. (canceled)
 24. A blood pressure measurement device comprising: anultrasonic transducer for transmitting a transmitted ultrasonic imagingsignal to a blood vessel and receiving a received ultrasonic imagingsignal from the blood vessel; and an audio transducer for transmittingan audio signal to the blood vessel, wherein the audio signal isconfigured to interfere with the received ultrasonic imaging signalbased on a model of the blood vessel response to the audio signal, andwherein the model correlates the received ultrasonic imaging signal withthe audio signal to generate a blood pressure measurement.
 25. Thedevice of claim 24, wherein the model correlates the received ultrasonicimaging signal with the audio signal by: i) convolving the receivedultrasonic imaging signal with a first weighting function to form aweighted ultrasonic imaging signal; ii) convolving the audio signal witha second weighting function to form a weighted audio signal; and iii)performing auto-correlation or cross-correlation on the weightedultrasonic imaging signal and the weighted audio signal to generate theblood pressure measurement.
 26. The device of claim 24, wherein thetransmitted ultrasonic imaging signal has a frequency within a range ofabout 100 kHz to 11 MHz.
 27. The device of claim 24, wherein the audiotransducer is a speaker.
 28. The device of claim 24, further comprisinga housing coupled to the ultrasonic transducer and the audio transducer.29. The device of claim 28, wherein either the ultrasonic transducer,the audio transducer, or both are detachably coupled to the housing. 30.The device of claim 24, further comprising a user interface foroperating the device.
 31. The device of claim 30, wherein the userinterface comprises a display.
 32. The device of claim 24, furthercomprising a signal processing unit.
 33. The device of claim 32, whereinthe signal processing unit outputs a signal processed measurement to asingle-pixel feature extraction unit.
 34. The device of claim 33,wherein the signal processing unit further outputs the signal processedmeasurement to an image processing unit.
 35. The device of claim 24,further comprising a wireless networking modality.
 36. The device ofclaim 35, wherein the wireless networking modality is configured tocommunicate the audio signal, the received ultrasonic imaging signal, orboth, to a peripheral device.
 37. The device of claim 36, wherein thewireless networking modality is configured to communicate a frequency ofthe audio signal to the peripheral device.
 38. The device of claim 24,wherein the audio signal has a frequency within a range of about 0.01 Hzto 3 kHz.